I don't know if you guys noticed or not, but when you step outside of your main city.. the single area map is about half the size of Vanadiel combined. Bit exaggeration there but you get the idea.

I'd have loved to walk outside Ul'Dah into the rocky areas, and venture off more towards the south and gradually see the environment transform into a true sandy desert (Altepa Deserts), or travel north and gradually climb higher into rockier more mountain like scenery, all on 1 map, all on 1 zone. Perhaps i'm not very creative to sound convincing with my details, but the general idea is there.