To combat people promoting their own tutorials and stuff, just have them include a short snippet as to what that resource concerns that others don't - what makes that resource worth visiting/reading?
I think that is valuable for sure, but I'd add that I would not have contributions via pull requests in this case. The reason is that there is some expectation when you go through the trouble of forking, cloning, editing, pushing back to the fork, and doing a pull request that your contribution will be accepted, and it very likely may not, which will result in anger, which is not a good thing.