This is an interesting topic. If for any reason we don't do a "top artists" section, it is not only because of the concerns (which I would have to give more thought to), but also because we don't have enough time. Right now we're putting together a moderation system, and after that, a jobs section.
Kirwyn--although I would agree with you normally that "downloads" could be a good indication, there are a lot of art/animation items on this site that are never "downloaded" per se, but only viewed. Having a double standard might give people more of an incentive to post artworks than other resources, which we definitely don't want. We may start a counter on who hits the "DOWNLOAD" button, though, just to keep track of things.
-Jake