You don't even have to decide right away. Even if you have her spend that refresh on new powers or stunts (yeah, stunts might even be more appropriate than powers), she might be on the road towards eventually gaining true free will, possibly as a function of some plot device which would lead to more adventures. If you think it's appropriate, she might even lose some powers, gaining the difference as refresh, to represent turning away from her old nature.
Or even if she gains some measure of free will, there's not necessarily anything stopping her from later deciding that she liked being a fae being better and blowing those points on some shiny new powers.
Even better: she starts getting some refresh, becoming more and more mortal as she grows closer to her new friends and family, but some crisis comes along and she needs more power; power which is available to her, if she only throws away her humanity and returns to being a wyldfae, or swears herself to the Summer (or Winter!) court. She saves the day, but loses the new life she fought so hard for.
Yeah, the right answer is whatever generates more hooks. Mo' refresh, mo' problems.