I wish someone would make a fantasy MMO similar to Eve Online's setup, so everyone plays together in the same world, but each zone could be hosted on its own server.

Think about it like this: if FFXIV was setup in this fashion, then they could redesign the game much easier than they could now. They could take the Black Shroud server down for a month or two, tweaking what needs to be tweaked, and even use in game lore to explain why the area is inaccessible, something like the Garleans invading and they're not allowing anyone in or out of the BS.