Up to 31 characters in the herostat (including defaultman). It hasn't crashed, but then again some characters are in "fake" menulocation slots (like 99). I'll worry about adding in proper menu locations later, but it looks like I can have 30 playables. Makes sense since there's 27 by default, then Moon Knight and Colossus (29), then defaultman (30), and then the fact that the game was going to include Longshot and Iron Fist at one point. That should mean (if I'm right) around 32 playables.