I really don't get the bad boy vibe from Dmitry at all. I admittedly never watched his season of SYTYCD (or any season, for that matter, I've mostly just watched some dance videos and interviews after the fact). But I think Maks's utter bluntness makes him seem "bad boy" when he really isn't, and I'm not expecting that particular flavor of forthrightness from Dmitry. I think he'll be just as serious about doing as well as possible as all of the other pros, but I'm thinking maybe we'll get a better sense of his personality watching him try to teach someone else. Here's hoping they're in the competition long enough for that, at least.
How about "Shirtless Wonder"
I don't know about that. It kind of makes one seem...deficient. Mentally speaking.
It should poke fun at his penchant for open/nonexistent-shirtedness: "Shirt Not Required", or "So He Thinks He Can Dance Without His Shirt", or something.
I don't have to tell you I'm one of the less clever people around, so other suggestions would no doubt be appreciated :)