Exploring the New Gotham
Zack Snyder has explained that Gotham City is Metropolis' sister city - it's located on the other side of the bay. If Man of Steel showcased a big, thriving city, and Suicide Squad aims to show the dark corner of the U.S. Government, The Batman - or whatever it will be called - could display just how much criminals thrive in Gotham.
Seeing Batman's city overflowing with corruption and violence has been witnessed in movies before, but this new Caped Crusader solo film offers the chance to focus on how one man holds a majority the power (Black Mask), especially since the Dark Knight has been absent for so long. The film can also fill Gotham with whole new variety of threats (e.g. metahumans and tech-savvy foes) and, hopefully, sprinkle in a number of promising easter eggs, too.
Personal Stakes & Batman's Moral Code
The stakes are often ridiculously high in comic book movies, and this is something Suicide Squad director/writer David Ayer has criticized. If inspired by Jason Todd's reemergence, the story would be all about morality and taking a good look at Batman's psyche. Batman isn't saving the city from being destroyed; he's facing his past and being forced to question how he operates. Batman is almost always able to save the day and he's a man with very few flaws, but having to deal with one of his greatest failures - one which could be the reason he decided to hang up his cape and cowl in the DCEU - offers a humanizing approach to the immensely talented hero.
Batman refusing to kill his extremely dangerous enemies can seem impractical to some, so why does he stand so confidently by his belief that he can't kill his villains? After all of his years of fighting crime, what has he really accomplished? Could Red Hood, a character willing to slaughter his opponents, do a better job protecting Gotham's citizens from the twisted scum that populates the city? These questions are front and center in the story, and it explains that Batman doesn't think killing is the hard choice... he thinks it would be too easy to do, and it's a method that he wouldn't be able to stop using. If he can justify killing Joker, who could he justify killing next? How much damage must someone do before Batman thinks it's okay for him to put the criminal down, once and for all?
Does Batman still hold onto this belief in the DCEU, though? The trailer shows Ben Affleck's Batman, in desert garb, snapping a soldier's neck, but an action figure hints at that scene being a nightmare. There also appears to be a scene, in the Batman V Superman teaser, of Batman's plane shooting at and in the process potentially killing gunmen - but if Lex Luthor is manipulating the two heroes, could he be using a drone to make Superman believe Batman's a killer?
In short, WB/DC making their version of Batman one who isn't strongly against killing can't be ruled out just yet. Still, making Affleck's Batman a man who is willing to severely hurt but not kill his enemies would bring about a conflict with Jason Todd that's far more compelling and remains truer to the comics.
Keep in mind, Batman's solo movie being inspired by Red Hood's story is just a rumor at this point. If it does happen, it may be loosely based on Winick's story from 2005, or it may show it a lot of love, like how Batman v Superman is including a lot of nods to Frank Miller's The Dark Knight Returns limited series.
Comic book movies almost always make significant changes from the source material, but Winick's story is able to successfully look forward and backwards - while also being full of engrossing drama, interesting character insight, exciting fights, and plenty of nods to a much, much larger world. If DC and WB can deliver those key elements, Batman's solo movie is sure to be memorable. If you don't believe us, do yourself a favor and watch the animated movie.
Batman V Superman: Dawn of Justice opens on March 25, 2016, followed by Suicide Squad on August 5, 2016; Wonder Woman on June 23, 2017; Justice League Part One on November 17, 2017; The Flash on March 23, 2018; Aquaman on July 27, 2018; Shazam on April 5, 2019; Justice League Part Two on June 14, 2019; Cyborg on April 3, 2020; and Green Lantern on June 19, 2020. The Superman and Batman solo films have release dates TBD.