Uldah has a nice bar... yep... I said it... damn Lalafel always standing by the Mi'qote on the table...

Anyways... jokes aside... like others said Ul'dah is most convenient right now since it' in the middle of the 3 countries. Gridania is nice looking but the Black Shroud just killed it. With airship in 1.19 and maybe like warp NPC within the city to teleport from edge of map to the other side like Windurst in FFXI would fix some problems why people don't want to be in other countries. But as game evolves like FFXI Jeuno or White Gate people will migrate to more convenient areas most likely.