We have echoed the thoughts of many other comic book fans, when it comes to our stance towards the issue of diversity in the Marvel Cinematic Universe; in short, the MCU needs more of it. The upcoming installments in Phase 2 will make progress on that front by introducing characters like Falcon in Captain America: The Winter Soldier and then Scarlet Witch in The Avengers: Age of Ultron, but as right now there's been no official confirmation that a Marvel superhero movie featuring a non-white and/or non-male protagonist will be made in the near future.
However, there has been the off-hand statement made by Marvel executives here and there in recent months, suggesting that the studio is taking steps to change that. First, Marvel Studios producer Louis D’Esposito acknowledged that there's "a drumbeat that is getting louder and louder" for a female superhero mainstay in the MCU. And now, it appears that Marvel could be developing a TV series based around Peggy Carter (Hayley Atwell in the Captain America movies) - one that builds on the foundation laid by Joss Whedon's Agents of S.H.I.E.L.D. (assuming the latter is a success when it premieres on ABC next week).
We can add Natalie Portman - who reprises as astrophysicist Jane Foster in Thor: The Dark World this fall - to the list of Marvel folk who've hinted that a female superhero move is in the works. Here is what the Oscar-winning actress said, during her interview with SciFiNow:
“There are definitely many strong women [in the MCU], but it will be exciting when there is a central female character which I think is coming - I have heard is coming - and, of course, also a central non-white character will also be exciting. Title characters."
Comic book legend and Marvel executive producer Stan Lee has continually name-dropped Black Panther as a comic book character who is going to get their own solo vehicle in the foreseeable future, but as of right now there doesn't seem to be much (if any) room for the Prince of Wakanda to be included in Phase 3 of the MCU (given the momentum that properties like Inhumans and Doctor Strange have on their sides, anyway). That's not to say a Marvel Studio release featuring a central non-white lead isn't part of the studio's plan leading up to Avengers 4 in 2021, but (as Portman implies) there seems to be a more likely chance that a female superhero standalone vehicle will hit the big screen first.
There's been talk over the years about Scarlett Johansson as Black Widow getting her own solo vehicle, but that seems unlikely to happen. In part, that's because it would appear that Natasha Romanoff is going to be (essentially) a central player alongside Steve Rogers (Chris Evans) in the Captain America sequel - leading up to her playing an important role in Avengers: Age of Ultron thereafter.
Beyond that, the most obvious choice for a female Marvel superhero flick is Ms. Marvel/Captain Marvel, with regard to the list of female comic book characters that Marvel Studios can actually include in the MCU (due to Fox and Sony owning the rights to many of the popular female Marvel superheroes). Fan-favorite Katee Sackhoff (Riddick) has expressed her interest in playing a couple of different comic book characters - including Typhoid Mary from Daredevil (the movie rights for which now belong to Marvel Studios) - and recently let it be known that Marvel has expressed an interest in collaborating with her... but almost certainly not on a new Daredevil movie, to prevent any confusion.
Would Katee Sackhoff be a good choice to play Ms./Captain Marvel in the MCU, or should the actress be cast as someone else? Better yet, forget which female characters are more likely to get their own standalone vehicle - who do you want to see featured as the lead in an upcoming Marvel female superhero film (be it a Phase 3 or Phase 4 installment)?
Thor: The Dark World opens in theaters on November 8th, 2013, followed thereafter by Captain America: The Winter Soldier on April 4th, 2014, Guardians of the Galaxy on August 1st, 2014, The Avengers: Age of Ultron on May 1st, 2015, Ant-Man on July 31st, 2015, and unannounced films for May 6th, 2016, July 8th, 2016 and May 5th, 2017.