5. Improve Upon Christian Bale's Batman Voice
Dawning a mask and cape can do wonders for your sense of self-worth, I'm sure, but there isn't a Batman fan out there who could justify that raspy, sometimes barely decipherable growl that Bale used when he became the caped crusader. Arguably one of the only points of contention with Christian Bale's otherwise fantastic representation of the Dark Knight, the voice is something Affleck can use to make his case that he can in fact cut it in a pair of tights and measure up to his predecessor.