Hmmm, well to be honest I think political correctness is an anathema, and as insane as they are not falling prey to it is one of the things I give Japan a lot of kudos for, even if they go in some truely bizzare directions with it.
That said, taken to it's extreme they might be onto something here taken to it's extreme. If you could get a bunch of deformed people, from radiation or otherwise, who could dance and sing at a high you could probably do a lot with it. Sort of like a carney side show, spliced with pop culture and stardom. The only real reason you haven't seen it, is that when people with deformities start to get too much attention the politically correct brigade jumps on it as explotive or pressures them to stop because of the plight of other people with unfortunate conditions but less oppertunities.
A heavy metal group full of grotesqly deformed mutants? It's not makeup because they are actually that way... watch out Lordi and GWAR if they can actually perform.