The best part about the Tinkerbell character in the film 'Peter Pan' was that she didn't talk. The animators had to convey what she was thinking or feeling through their drawings without the aid of her saying something. I always found that to be a brilliant element in the film itself.
Now Luann from 'King of the Hill' is going to be her voice. I just don't know. It may work, but I'm thinking it most likely won't. Maybe Murphy could revisit her character from 'Clueless' for inspiration for the voice.
"Cher, I don't want to do this anymore. And my buns: they don't feel nothin' like steel."