Hmm... to me, the banners already have a good range from popular to lesser known artists. I'm not the be-all end-all of how well-known artists are, but these artists range from from Blotch (well-known, of course
) to Clawed, whom I'd never heard of before. Both artists are very talented, but if you were to judge popularity by pageviews alone, Blotch has 75,000 in the space of a year or so, and Clawed has about 7000 in the same period, more or less. (I like both their styles, and since I hadn't discovered Clawed before, I was glad he was chosen to make the banner.)
So it sounds to me like it's less about popularity itself to you and more about, um, quality. Or lack thereof. I like seeing the high-quality banners the way they are now, but I guess we'll see what Preyfar thinks. I think they're his domain as Dave said.