User Amenities/Feature Unlocking by participation
The topic pretty much says it all, but I'll break it down in layman's. I suggested this YEARS ago on the forum, but probably didn't put much effort into pushing the agenda.
Let each account start out with something like... one picture, one outside link, and one track. Then, for every 5-10 ratings you do, you get to unlock one more. In conjunction with the ratings system changes I already suggested, this would make it beneficial that not only are they actively participating (which I always felt was a strong point that was lacking in the initial build), but it's helping others out by getting more worthwhile opinions on their material. The minimum word count would definitely have to be a part of it so as to cut out the gassing or easy feature unlocks by rating something and throwing "Dope" in the comments and calling it a review. The more you do, the more you can do. For non-artists, give things like access to downloads or exclusive content people who don't participate don't receive.