In Echo, the main character, which is Echo, is mute from birth. She doesn't use sign language because no one understand it, and writes on paper instead. (and I must say I also know very, very little about using sign-language, though it's a language I'd like to learn)
Hrodland got night terrors and depression. It's still not a big disable, but it can drive crazy or even more depressed. This also explain why he's reluctant at talking to people and always angry. He lacks of sleep right now in the story.
The archmage is an albino, does it count? XD He can't stay where there is light, but he tries to protect himself with his cloak if he has to meet someone. Otherwise, he stays in the dark all day, making him even more frightening than what he is already.
At least four characters are one-eyed (three "main" and one very minor), one of them got a glass eye. Another one (a very, very minor) is mute because of his tongue cut. One minor character is half deaf, iirc... but I don't remember who it is... (bad, bad me)
And I'm working on a villain with a trauma that lead him crazy.
... got a lot of disable characters, with a higher rate for the one-eyed guys... XD
As a lot of them are warriors, they got scars and maybe lost something, so it's quite normal.