They should chop the zones up into like 6-7 pieces each and redesign the pieces one at a time. Lock them off with invisible walls while they're still being redesigned. The world size right now is plenty huge and most of the space is unused. If they leave the world as it is they will be trying to fill this huge world via breadcrumb updates. One zone in XIV is like the size of an entire world other MMOs release with, this really is excessive.

Since there's like no content in the game right now it's a good time to chop them up so they dont have to go changing quests and stuff later. I'm pretty sure they will have to do this eventually either way.