Speaking of a gang war, and especially as this may be taking some inspiration from The Long Halloween, I'd really like to finally get an overall world-building arc of the old-school traditional mobsters like Falcone and Maroni being replaced with the "freaks" and the rise of characters like Joker, Penguin, Mad Hatter, whoever exactly is in this movie/series.
The Dark Knight had a little of that with Joker and Two-Face killing the mob bosses, but they have a chance to do a lot more with that idea, especially with the characters they're setting up here and the themes of evolution Reeves talked about.