Especially when it comes to character generation, I’ve found over the years that the best approach for PC options, abilities and funky tweaks that you think might be game-breaking is to allow them, and dial them back if you turn out to be right.
This doesn’t apply to things that are obvious game-wreckers, or to players who are clearly out to bend the rules to the extreme. But if you’re not sure, why not allow it and see what happens? Just make it clear up front that if it breaks the game, it’s going the way of the dodo.
Do you agree, or do you prefer a different approach in this situation?