The title says it all. I can't see it being too difficult to implement, but I'm not a developer. I have, however, seen plenty of people being upset with this not being possible. It'd be really nice to change that hairstyle you thought looked good, but really didn't, once you got in the game, right? I wouldn't even mind if it was added in the next DLC. If it wasn't, that'd be fine, too. That'd just make the game better, to me. People don't want to have to make new characters, just to get a new look. I think a lot of people made characters with the assumption that they'd be able to change their look at the Tower.