Teleports do seem like a major issue. I think that's something that needs to be met head on, rather than trying to make content that can't be exploited by it (really, teleporting hacks are so powerful you can't really do that). They faced that in FFXI and mostly dealt with it, so maybe that won't be a concern.

FATEs being limited would create some tension there, but I think locking people out is the lesser evil, especially if in the long it means less FATE camping altogether. I think I may have a solution for FATE camping, though:

I didn't want to include this solution, since I'm iffy on it, but one solution would be to generally lower FATE EXP (especially, for the high end reward ones) and add a daily quest/hunting log system that gives each player a unique and random list of FATEs scattered around the world to do. The EXP awarded for completing these FATEs could more than make up for the EXP nerf (with even objectives asking players to do low level FATEs giving good rewards). The end result would be more FATEs mattering: more variety, less ignored content, and less congested/dead areas. If I wanted to synchronize it with my other changes, I'd have the NPCs responsible for this system be one of the NPCs that can be captured during "defend the area" FATEs (e.g. Attack on Highbridge).