I wonder, why not allow LFG or even random players out in the world to give either a rating or a "Like" or such to WoW players.
Not only would this be some sort of "good behavior" achievement that would encourage players to help each other, maybe add in a reward like, some event or content, etc. for the most helpful players each month, etc.?
TLDR: why not democratically encourage good behavior, instead of pure greed?