There's been a lot of different kinds of exploitations that's been undermining the game as of late. These involve warping (from one node point to another, from one location to another, without the use of an Aetheryte Crystal), botting and other forms of exploitation. I've seen the warp exploitations myself, brazenly being used out where everyone should be able to see them, but either gets unreported due to apathy or that other players are also enaged in similar behavior.

If you want to know what is causing a lot of server instabilities, you might want to beef up your support staff that reviews the "cheating" tickets. Many players, myself included, have reported all sorts of things that are not limited to RMT spamming in chat. And I know some groups have even used these illicit programs for end game purposes.