Radio based on artist is already under the works, we should have that out soon.

Variable pricing does seem like a good option. We'll have to explore this further & see how that goes well with the artists. Because they and they alone control the pricing for now. We however do a have a "pay what you want" feature right now, something people have used more often than not.

Again, thanks for the great feedback. I have your email, would like to send you free invite to preemium features once we have them out.