Forcing a slow leveling would be the best way to deal with this. Nerf Fate xp by 90%.
Nerf Tomestone drops by 70-80%.

Make everything too painful for those who only rush and have no plans to play this game over a longer period of time.

There's plenty of other MMO's out there where you can get to max level in a day and stand around in a circle with all your other max geared pals showing off your epeen, tellin less-geared and new players "l2p".

And just think of the shitstorm on the forums, it would be something to behold!