I find it hard to take seriously the idea that someone would actually choose death. That seems awfully stupid to me.
It would be a hard choice for me between deafness or blindness. Being deaf would obviously be much easier in the short term. It's not too difficult to build a life without sound, but without being able to see even the simplest things would have to be relearned. Blindness also completely omits more options, such as video games... or driving. I would seriously have a hard time not being able to drive. Music is awesome, and I'd hate to lose it, but I'd lose more by being blind.
On the other hand, long term it seems to me that being deaf would make the world feel hollow. Life would be the same but worse, if you can see what I mean. Blindness would change everything. Independence would be extremely difficult, but I kinda feel like I'd rather start over than just have everything be worse, you know? Being blind would be a challenge. It would suck, but so would being deaf, and despite the fact that blindness is pretty much completely worse than deafness, I feel like I would probably end up being a happier, healthier person if I were blind.
I dunno, I'm probably over-thinking it, but I'd choose to be blind.
Also, there is no universal cure for either blindness or deafness, because there is no universal cause for blindness or deafness, so it's pretty silly to pick one of these because it'll be cured soon. It doesn't help to have a replacement ear if your cochlear nerve is destroyed.