But... I also question how much anger and hatred this is going to produce. Ultimately, I guess it's all just speculation. People respond very differently to the exact same stimulus, and one reaction isn't necessarily any more valid or likely than another. But that's what my mind immediately thinks about--what reaction he's going to have to being blinded. Will he feel the punishment is unfair and seek even more revenge? He may not be able to hurt her himself, being blind, but he's probably got friends--he could theoretically have someone else do his dirty work for him, and it might not just be the blind woman who's terrorized, but her family and friends as well. I don't know if my ponderings produce anything, but I just speculate about the various responses he might have.
Humans have a way of rationalizing anything, and they always rationalize things so that they are benefitted by it in some way--they're biased in favor of themselves. Just because he's put through the same thing doesn't necessarily mean he'll be made more empathetic.
I like what someone said about it maybe being a worse fate not to be punished for his wrongs. Don't give him a reason to feel he made up for anything, don't give him a reason to say, "I paid for my crime," or a reason to feel sorry for himself. Just see if the guilt does him worse over time than anything else anyone might have done to him. Maybe it'll be a ticking time bomb, something that gnaws away at his guts and decimates his self-respect. Possible.
Edit: I guess I approach this mostly from the perspective of wanting him to learn something from this experience, to be rehabilitated. I feel bad for her, and I'd want what ultimately benefitted her the most, but I need to balance what's going to benefit her with what's going to benefit everyone else, too--including our villain. Because I think what truly benefits him is going to benefit everyone else.