From what I've seen, the gay/lesbian sidekick is the one who's usually hip/cool/trendy/funny - though as you pointed out, "Black male/female" fills this role, too.
You left out the "Worldly, Wise, Measured, Older Black Male", who is smarter/superior in every way to the dumb white guy. To wit, think "Every single role Morgan Freeman has ever played".
And don't forget the kids, who are always smarter than the dad. Always.
I believe that shawshank redemption kind of flips that stereotype on its head where Freeman is concerned.