since its a storybase game, i must admit that a bit of freedom could be fun on certain point, but its still a video game with code line and not player talking around a table, so it has to be limit for what they are program to do . so ....
class, race, backstory got to be fix.
appearance could be changed. its not like if shadowheart have black or white hair change a lots, i dont know the whole story but , unless theres info (book,random lore) talking about them without naming them, i dont think its a huge matter
subclass can already be chosen(except for wyll since the choice of warlock is at character creation, but storywise , he need the devil class. and the pact of chain is the only avalaible pact right now)
ability, base on a point buy is kinda good on a ''general'' view, but for more team customization, it would be great to be able to place them ourself, if you want a tanky or a caster shadowheart or a archer laezel.
and character sex : might be more heavy for the programing team if theres instance where they are threat base on their sex. like romance scene, but im not far enough to provide a answer for that point.
if you REALLY want a custom team, i must admit that a ''mercenary board'' thats let you hire/buy mercenarie that you create could be interesting, but right now, i think that you can create a multiplayer game with your friends, let them create the character you want, launch the game, and then, they quit, leaving you with a fully custom nonstory guided team.
