Oh yeah, I like the idea of grafts. I say have it done against her will by some half-crazed artificer. Once she escapes his clutches, he'll constantly be sending other constructs to recapture his beloved. "Ooh, those giant steam powered arms are so sexy. Come to daddy."
My guideline is that anything that directly and permanently changes a character's nature -- bodily or mentally -- really needs to be discussed with the player. Nothing is more annoying than having the GM mess with your character.
Despite everything I have posted previously, I completely agree with you. I once had a character lose three toes to some cannibal pygmies who had captured her. I did not like that at all.
Whatever DM is running Battlestar Galactica sure had a fun time with Boomer. That could be a great deal of fun if you had a character who could roleplay it properly.