Initially, i believe that "contributor" is not the best name. Me and some friends when stated thought it was simply who put $$ in the game.
Maybe "helper", "tutor" is more appropriate.
I do not know if it has a connection, but many contributions that you have talked are referring to the marketing, such as events, guides and videos. I do not see this as something good for something as a "contributor", despite having an indirect connection, guess is its just a extra thing, and not the hole thing.
Besides that, i think ranks are a nice thing, which provides the growth and the "keep being a contributor desire".
I love the suggestion, but removing the events, guides and videos extra importance. And the name... cant like "contributor". Life is without colour with that name :(
Sorry if i write something wrong, or it seems that i did not like the idea. Its a great suggestion.