For the past 10 years (and probably the next 10, too), the Marvel Cinematic Universe has entertained millions of superhero fans, whether they be long-time comic book readers or new fans with no clue who the Guardians of the Galaxy were before Marvel brought them to the big screen.
However, when the MCU started, it had nowhere near the fanbase or solid future that it has today, with several of its Phase 1 movies receiving mildly positive reviews from critics.
So, what is the MCU's secret to success? Besides the great writing and enjoyable action, it's the characters.
While other cinematic universes spend more time plotting out their franchise's future (some before they even get a second film), the MCU's producers try to find who they believe to be the perfect actors to portray Marvel's large gallery of heroes and villains.
When Robert Downey Jr. was cast as Tony Stark, fans were furious. Now, 10 years have passed and nobody else comes to mind when thinking of Iron Man.
This has led to many fans creating their own dream casts for the MCU, some improbable, some with cool ideas, and some even predicting the real casting choices.
While the MCU cast has been pretty solid so far, it's nice to dream a little and look at what could have been.
With that said, here are the 25 MCU Fan Castings Better Than What We Got.
25 Gal Gadot - Sif
Israeli actress Gal Gadot proved a lot of critics wrong when she took the role of Wonder Woman and became one of the highlights of 2016's Batman v. Superman: Dawn of Justice.
Since then, she's been perfect as DC's Amazonian princess.
Since Gadot already does great as a sword-wielding goddess, Marvel's Norse goddess Sif would surely be a walk in the Asgardian park.
However, Jaimie Alexander's Sif has so far only had supporting roles in two Thor movies (compared to Gadot's soon-to-be three starring roles).
So, having Gadot serve as backup to Chris Hemsworth's Thor instead of as the female icon we love her for would certainly have been a step backwards.
However, it still would be an incredible casting decision.
24 Rami Malek - Bucky Barnes/Winter Soldier
A brainwashed assassin with a cybernetic arm? The star of an award-winning techno thriller called Mr. Robot? They're perfect together.
Okay, so that's not the reason Rami Malek would've made a good Bucky Barnes.
However, the aforementioned show along with his seemingly-breakout film performance as former Queen lead singer Freddie Mercury in the upcoming biopic Bohemian Rhapsody, gives us the impression that he would've had the acting chops to fit right in as Steve Rogers' best friend.
Although, Sebastian Stan is clearly in love with his role, and we are, too.
23 Meryl Streep - Aunt May
Casting one of the most nominated actresses of all time couldn't hurt the MCU, right?
While Spider-Man's aunt may not be a superhero, she still serves as his alter-ego's sole guardian and moral support.
With this, Meryl Streep could offer a lot of inspiring advice to both Peter and the audience.
Marisa Tomei is playing May for now, but some audiences are still having trouble getting used to her performance.
Besides being way younger than her comic counterparts, she hasn't proven herself quite the scene-stealer as Rosemary Harris (or even Sally Field).
Even though Streep isn't known for many long-term roles in franchises, we can keep our fingers crossed Sony gives her a chance in their universe.
22 Jessica Chastain - Pepper Potts
Being Tony Stark's girlfriend and fiancé isn't easy. One minute, you're an assistant. Next, you're CEO.
Then, you're in an on-again-off-again relationship that makes fans wonder when her next movie appearance will be.
However, Oscar-nominated actress Jessica Chastain can certainly handle pressure (since starring in six films in the same year is no small feat).
Plus, it helps that Chastain's appearance is pretty spot-on for Pepper (being a natural redhead helps).
While Gwyneth Paltrow hasn't been doing bad at all, one certainly has to wonder how Chastain would've fared.
Here's hoping Marvel does her right with her supporting role in next year's Dark Phoenix.
21 Chow Yun-fat - The Ancient One
Yes, it would've been nice for Marvel to have cast a Chinese actor for the role of Stephen Strange's mentor.
However, that's not the only reason Chow Yun-fat could've worked as The Ancient One.
Yun-fat's career consists of several critically-acclaimed action flicks, including the Best Picture-nominated Crouching Tiger, Hidden Dragon.
While The Ancient One is not known for his physical fighting, Yun-fat could certainly bring some unique move sets when conjuring magic as the Sorcerer Supreme.
Despite this, Tilda Swinton did a good job of making the character her own and further adding to the sorcerer's mysterious history.
20 Mads Mikkelsen - Malekith
Actor Mads Mikkelsen is known for his villainous roles, including Casino Royale's Le Chiffre and Dr. Hannibal Lecter in the regretfully-cancelled hit NBC series.
So, it wasn't long before he got snatched up for an MCU villain, even though it may not have been what fans were expecting.
Mikkelsen certainly did a fine job bringing the lesser-known Marvel villain Kaecilius to the big screen, but that was primarily because of the actor's intimidating presence.
In fact, if Marvel were to have given him the makeup treatment instead of Christopher Eccleston, Thor: The Dark World could've turned out better with a downright demonic antagonist.
19 Mary Elizabeth Winstead - Maria Hill
While it's always cool to see actress Colbie Smulders playing Nick Fury's S.H.I.E.L.D. sidekick, it's hard to look at her and not see Robin Scherbatsky.
Meanwhile, Mary Elizabeth Winstead is no stranger to playing multiple unique roles, including John McClane's daughter Lucy in the Die Hard series, Scott Pilgrim's delivery girl-friend Ramona Flowers, and even former First Lady Mary Todd Lincoln in Abraham Lincoln: Vampire Hunter.
Though Winstead said she's not very attracted to multi-movie roles, she does want to work with Joss Whedon, who directed Hill's debut in The Avengers.
18 Tony Todd - Ronan the Accuser
With one of the most evil-sounding voices in the business today, actor Tony Todd could've easily brought a different level of intimidation to the Kree fanatic.
Lee Pace's forgettable performance didn't quite live up to what he described as a "psycho" and "monster."
However, with Todd in the role, audiences would've been cowering in fear every time he opened his mouth.
Todd has already put his voice to good use for DC, voicing Zoom in the second season of The Flash and Darkseid in two Lego DC Comics Super Heroes films.
17 Patrick Wilson - Darren Cross/Yellowjacket
Cross Technologies CEO Darren Cross was certainly an evil character in 2015's Ant-Man (who else would hurt a tiny lamb?).
However, Corey Stoll isn't the only actor who can pull off playing a mean guy in an odd-looking suit.
Wilson also has experience wearing a suit, as he played retired superhero Nite Owl in 2009's Watchmen.
16 Matt Smith - Vision
Already an icon in geek culture thanks to his acclaimed run as Doctor Who's Eleventh Doctor, actor Matt Smith could have been a welcome addition to the MCU as the red-skinned android with a British accent, Vision.
While he would've had to push his energetic attitude aside (and trade his Sonic Screwdriver for an Infinity Stone) when playing the straight-faced Vision,
Smith has already proven he can handle dramatic roles, such as his Emmy-nominated turn as Prince Philip, Duke of Edinburgh, in Netflix's The Crown.
Unfortunately, instead of debuting as Vision in 2015's Avengers: Age of Ultron, Smith chose to act in the sci-fi failure Terminator Genisys (which is being ignored by Terminator 6 anyways).
15 Rashida Jones - Hope van Dyne/Wasp
However, while she took part in funny moments of the two moviea, Lilly is more known for her dramatic performances, particularly Kate Austen in Lost.
To be the mature one in the superhero duo while also having to properly trade quips with a comedy legend like Rudd, someone like Rashida Jones would be perfect.
For one thing, she has co-starred with Rudd in comedies I Love You, Man and Our Idiot Brother.
14 Emily Blunt - Carol Danvers/Captain Marvel
It may not be exactly fair to be talking about a different casting choice when actress Brie Larson's portrayal of the red-and-blue-clad Carol Danvers hasn't even hit screens yet, but hear us out.
Blunt even sat down with Vulture to discuss the Captain Marvel fan castings, which she said were "always very nice."
Even though Blunt won't be soaring through the air as Carol Danvers, she will take to the skies with a trusty umbrella as child icon Mary Poppins this December.
13 Joseph Gordon-Levitt - Scott Lang/Ant-Man
This Golden Globe-nominated actor has certainly had a fun movie career.
With his first film role being in the cult classic Beethoven, Joseph Gordon-Levitt has since gone on to star in Inception, (500) Days of Summer, G.I. Joe: The Rise of Cobra, and The Dark Knight Rises.
However, both Rudd and Gordon-Levitt are both funny, yet dramatic guys, so both are good choices for various superhero roles the world can throw at them.
12 Peter Cullen - Ego the Living Planet
Actor Peter Cullen is known for bringing many popular cartoon characters to life, including Optimus Prime and Eeyore.
While voice actors are not usually given major roles in blockbusters, they are still just as able to play superheroes and villains as any other actor.
Case in point: after Ego's face appeared on his planet's surface (like it does in the comics) in Guardians of the Galaxy Vol. 2, the film immediately cuts back to what's happening on the planet.
Cullen's voice would've been nice to hear coming out of the giant planet, even if only for a few minutes.
Plus, he isn't without superhero voice work, as he voiced various characters in two '80s Spider-Man cartoons.
11 Ron Perlman - Thanos
Okay, put down your pitchforks. Actor Josh Brolin has been doing great as Thanos (even better than Deadpool's metal-armed adversary/partner Cable).
Mainly, his desire to wipe out half the universe to impress Death herself.
While Brolin made Thanos a sympathetic-yet-mad antagonist for the MCU to build up to, if the producers wanted to fall more in line with the comics, Ron Perlman would've been great.
His deep, intimidating voice alone is enough to frighten any Avenger.
Add that with his live-action chameleonic portrayals of Hellboy, and we've got a winner for the Mad Titan.
10 Sofia Boutella - Elektra Natchios
However, who's to say Sofia Boutella, an accomplished French-Algerian actress, dancer, and model, couldn't give the sai-wielding mercenary a go?
No stranger to blockbuster franchises, Boutella has graced the screens as blade-footed assassin Gazelle Kingsman: The Secret Service, alien scavenger Jaylah Star Trek Beyond, and murderous Egyptian princess Ahmanet in 2017's The Mummy (well, maybe not that one).
With this in mind, playing the love interest for one of Marvel's most violent heroes would certainly be fun to see.
9 Vin Diesel - Black Bolt
When an Inhumans movie was announced for Phase 3, actor Vin Diesel teased fans of his involvement as the scarcely-speaking superhero.
However, when it switched to TV, Anson Mount was cast instead.
While Mount wasn't the main reason for the series' failure, fans probably would've preferred Diesel in the role.
Even though he is already a part of the MCU (as talking tree Groot), audiences only hear Diesel's voice and see his motion capture performances.
Wouldn't it be nice to see him in the flesh?
Also, the reason Black Bolt doesn't talk much is because his voice sends out powerful shockwaves, which sounds like a perfect excuse to use Diesel's deep vocals in some action scenes.
8 Ciarán Hinds - Justin Hammer
In the comics, Justin Hammer is the man responsible for several of Iron Man's enemies' access to advanced technology.
While Sam Rockwell is a talented actor (recently winning an Oscar for Three Billboards Outside of Ebbing, Missouri), he played a younger Hammer more like a slightly-evil Tony Stark clone who let Mickey Rourke's Whiplash do all the work.
To give us an eviler and closer-in-age representation, Irish actor Ciarán Hinds would've been great.
Hinds has already tried and failed at playing major antagonists for both Marvel (Mephistopheles in Ghost Rider: Spirit of Vengeance) and DC (Steppenwolf in Justice League), but this doesn't mean he wouldn't have proven a formidable business rival for Tony Stark.
7 Alexander Ludwig - Clint Barton/Hawkeye
Hawkeye may not be the most prominent member of the Avengers, but actor Jeremy Renner has given him likeability with his portrayal of a family man just doing his job (his absence was certainly felt in Infinity War).
However, Renner is getting older and can't play the arrow-shooting Avenger forever.
Meanwhile, Alexander Ludwig, known for action roles in The Hunger Games and Vikings, sits at only 26 years old.
While this would leave him with a major age gap with the rest of the Avengers (he would've been barely pushing 19 for Hawkeye's debut in Thor), he would've still had the looks, experience, and potential to play a long-lasting Clint Barton in the franchise.
6 Abigail Breslin - Crystal
Again, changing one Inhumans character wouldn't have been enough to save the series, but giving young actress Abigail Breslin the role of the Royal Family's element-controlling youngest member does sound better than what we got.
While Breslin's name isn't as household as some of the other MCU stars, she certainly has star power when playing younger siblings, as evidenced by Little Rock in Zombieland and her Oscar-nominated role of Olive Hoover in Little Miss Sunshine.
Because of this, it would've made perfect sense to cast her as Medusa's younger sister.
5 Harry Shum Jr. - Danny Rand/Iron Fist
Another of Marvel's TV failures, when the first season of Iron Fist premiered last year, fans and critics agreed that Jones' performance was a negative aspect of the show.
While there was controversy over whether Iron Fist should've been Asian or white, casting Chinese American actor Harry Shum Jr. wouldn't have been a bad choice.
4 Hiroyuki Sanada - The Mandarin
Here's a fan cast most Marvel fans will agree with.
In Iron Man 3, a lot of fans were disappointed when the antagonist they were promised via actor Ben Kingsley's Mandarin turned out to be an impersonator, and the real villain was a no-show.
The Mandarin is Iron Man's arch-enemy, portrayed as a megalomaniac scientist, martial artist, and magician.
While we would've loved to see Kingsley's take on the character, perhaps Hiroyuki Sanada would've been more accurate.
One of his best-known roles was the kendo-trained supervillain Shingen Yashida in The Wolverine. This alone gives us confidence he would do great.
However, we may get our wish, as Sanada is cast for a mystery role in Avengers 4.
3 Elena Satine - Natasha Romanoff/Black Widow
Scarlett Johansson's role as Natasha Romanoff is one of the highlights of the MCU (even landing her own solo film), and it would be difficult to imagine anyone taking her place.
However, Johansson is a busy actress, with several roles in award-winning films and plays already under her belt (and hopefully more to come).
To avoid putting too much on the actress' plate, what about using an up-and-coming actress with multiple superhero roles under her belt?
Having played Aquaman's wife Mera in Smallville, Asgardian Lorelei in Agents of S.H.I.E.L.D., and psychic mutant Beautiful Dreamer in The Gifted, Elena Satine seems like a pretty great second choice to consider.
2 Charlie Hunnam - Thor Odinson
Another actor we couldn't imagine taking out of the MCU, Chris Hemsworth has made the God of Thunder his own with three successful solo movies and acclaimed starring roles in all three Avengers films.
However, English actor Charlie Hunnam isn't a bad choice either.
He previously tried to start an action franchise with King Arthur: Legend of the Sword, throwing 1000 punches a day in preparation.
However, we all know that didn't turn out as planned, and Hunnam's chance at a legendary hero will have to wait for now.
1 Matt Bomer - Tony Stark/Iron Man
Finally, we have the most controversial fan cast on this list.
While many fan casts were made before actor Robert Downey Jr. was cast as Iron Man, not a lot have been made since because of Downey's near-perfection in the role.
However, casting Downey was a risk at first due to his troubled past.
Though he has certainly redeemed himself, had Downey passed on the role, a great runner-up would've been Matt Bomer.
An attractive Golden Globe winner, it's not hard to see that Bomer could pull off a "genius, billionaire, playboy, philanthropist.
Plus, he voiced another comic legend in 2013's animated movie Superman: Unbound. Three guesses for who it was.
What do you think? Who are your favorite picks for the MCU? Let us know in the comment section!