I've gotta say, I've only been to three appropriate raves, and while I agree with you in theory, practically I've not seen it. The Anime Club Dance, while cool, and exactly what you guys suggest: lots of geeky people dancing to anime and para-para and eurobeat... with Luke DJing and keeping it interesting, but nobody danced. Aside from just about everybody in the room getting rolled up into the katamari congo line, it was mostly just the same 8-10 people raving with occasional other people busting a few moves. It was hard to get all the people on the floor.
At Tora-con, all I saw was regular techno-rave stuff. However, it was really thumping. The Cheat was being thrown around with lots of glowsticks and everything you despised: But it was thumping.
Then at anime boston, it was half and half, but the anime stuff seemed decidedly less fun. But I didn't stick around for that much...
I'd love to see more of the Anime music raves, but I've just not seen them work. Anyone want to contradict me? I'd love to hear of a good anime rave, because that'd just be awesome.