Battling Siki Saad Schmeling (if done properly) Ketchel Kid McCoy Les Darcy Some of them wouldn't exactly be feel-good affairs though...
Probably because he's not really had that interesting a life compared to other fighters, even though he is probably a more interesting character.
Victor Ortiz and his story he told us on 24/7. But then again, it wouldn't be a biopic since it'd be fictional.
There are a lot of names that could merit a bio-pic. Most boxers and good films share in common an excess of things, from adversary/adversaries, triumph/redemption etc, etc..