Gated behind story. - Let's say you grinded the last 4 levels to 50 on beastman dailies, but then you learn that you can't do things, like Hildebrand or CT, because you have to finish the story. (But, hey, at least I'm no longer stuck behind storymode-Garuda).

A lack of a more efficient/ convenient means to report and block RMT spam. (At least it's not like Aion's.)