Flight training is key here. I know what you are thinking....she already knows how to fly. What I mean by flight training is teaching her to fly in a controlled manner, thus gaining confidence, and improving flight ability. This is what I did with Oscar (he is on one of his flight perches in picture). He was a horrible flyer when I got him as a rehome, who had been previously clipped. He could fly but only if scared and it ended up him hitting walls, chairs, doors etc. He was going to kill himself if I didnt intervene. What I did is start to research online and came across theparrotforum.com and Michael's blogs/videos on flight training. I suck at posting links but much better to train rather than handicap the bird.
As an illustration Oscar is now a very good confident flyer who now enjoys his nightly flight sessions, flight recall, flighted retrieve etc. His behaviour is like night and day as well since he has become a proficient flyer.
I think this is the most responsible route and the bird doesnt suffer AND you improve your bond through training bird.
Hope this helps,
Wayne