In Which I Wonder What Is Too Much

'm toying with a new idea for a character in "Penny's Luck". Cal, her boyfriend (Penny would say, "he's not my boyfriend", but he will be, she just doesn't know it yet). Anyway, Cal is 16, can drive a car (so he's frequently Penny's ride to and from work), and used to be a pretty good gymnast. He shot up over a foot in the last year, so he can't do gymnastics any more, but the high school coach is pushing him to do pole vaulting or high diving (or both!)

Because his center of gravity has changed so quickly, and his arms and legs are longer than his brain is used to (yet), he's also a little clumsy. He bangs into things or knocks things over. A lot.

I like Cal, and he ends up getting kidnapped with Penny at one point. I want him to be more than just comic relief. I want people to see why Penny would end up with him. I also want him to have a skill that Penny doesn't have. (Her skills are sleight of hand and misdirection.) I think I want Cal to be deaf. He had meningitis a  few years ago, and became deaf as a result of it. His skill would be lip reading.

I don't want his deafness to be a big issue in the book. He's a just a teenage boy, who has a crush on a girl, and he happens to be deaf.

I'm playing with the idea for now, but my worries are:

1. Deaf culture. I know enough about the deaf culture to know that deaf people aren't as simple as "create hearing character, remove hearing". I'm also big on people not writing about minority subcultures without an understanding of that subculture. (I know I hate it when my religion is misrepresented in fiction.) Can I learn enough about the deaf subculture to do a credible job of creating Cal? 
2. Is it too much? Is making Cal be deaf a "kitchen sink" problem, where I'm just putting too many elements in the story? 

I think it makes the story stronger, but I may not have the chops to write it well. I guess I'll have to try and see if I can pull it off. If anyone has any thoughts or advice on the subject, I'd love to hear it!