Depends on what you want to do.
PvP? Farm?
For PvP, what I have done is I have a mage (Now working on dexxers) on every west coast server so that I can raid spawns if I find them being worked. Also GL is a good place to be if you don't want to waste time at yew gate (Which is about all Atl is good for), GL has some decent dungeon fights.
Farming? Baja, Napa, Pac, Chessy are all near dead servers (Hell, most west coast servers are dead).