A little story I thought I'd shre with you - When we built the first two chracters for our current game, the players decided they wanted to roll for EVERYTHING, I mean like - Eye color, height, age, everything. What's interesting, in Fabled Lands there's also a table for your personality, with "good" and "bad" qualities (like laziness, beng a liar, kindness etc.), so they decided to roll for that as well. You know, for laughs. But this turned out rather interesting - The characters suddenly got new twists, new concepts were created and generally character creation was much more fun. So we decided to make these rolls mandatory, but that they're not binding (if you got a roll you don't like you can ignore it or change it, or roll again).
I heartly recommend it. If you ever feel like the characters are getting sort of the same orthat your players aren't being creative enough, make the players roll everything - From looks to personality, in a way that's not binding. It'll at least get them thinking about their characters more. For example: One of our players rolled that his character was both compassionate and a liar, which he didn't like at all at first, and more than that, couldn't quite understand how the two work together. But once he figured that out, he loved the idea and decided to do with it for his character.
My group is very hard on thr role playing, we always think very hard on our characters. Despite our initial fears, these rolls don't replace that, they actually complement it very well.