Well, I'm not a parent, in fact, I'm still only a highschool student. But I also have had ADHD since I was 10, and I thought I could explain some of the benefits I get in school as a result of it. I'm also a martial artist so I have that experience too. Karate is one of the best ways to treat ADHD without meds, so its great that he is in it!
Anyway, my problem is my lack of focus, I also require additional time when I take tests. For example, on the ACT, I was able to get additional time with no extra charge because of my ADHD, so he shouldn't be denied that. Also, throughout my entire highschool career, I've been able to get additional time on most of my tests in general, along with extra after school help. I attend a public school, and here we have some sort of requirement to allow specific accommodations for students like me who need it.
Not sure how much help it is, but he should be able to get extra help in school/extra time for tests if he needs it. I would assume that there would be similar circumstances should he get the diagnosis of Aspergers too.
In regards to the social issues, it doesn't sound too serious. However, if things progress, I'd suggest considering a psychiatrist of some sorts if you'd be okay with that. I've never needed one personally, but I've known people with ADHD who've seen progress as a result.
I know ADHD can be difficult to handle, but with the right accommodations, its very livable. Just be sure to continue to stand by his side when he needs it!