OK, definitely not any sort of expert on chicken varieties. But this one looks like it might have some sort of Japanese variety mixed in. Maybe a black tailed buff Japanese??? Not a purebred I don't think, but he looks a aweful lot like a couple of the roosters running around in the background of a few photos my son was showing me the other day. From one of his trips to Japan. If he had a longer tail maybe a Chubalaya mix. His legs don't look long enough though. This is fun!
You certainly have quite a few beautiful roosters.