IMO VTs are VTs - you can't improve it. But you can use it to lengthen other fin types.
From where I'm sitting, he looks like a combination between copper and yellow (correct me if the picture doesn't do him justice). If you breed him to a dark color, you will probably lose the yellow or only have yellow on the fins (regardless whether he is copper or black). If you want to keep the yellow, breed him to another yellow, orange, or a red cambodian. White opaques may produce few yellows, but probably with irid colors (blue).