Indeed, it would be a most welcome change.

Currently the three primary cities are heavily favored as home or free-teleport points due to their inter-world travel function.
Say I'm in Old Sharlayan and wish to join another world's hunt train starting in Labyrinthos, I have to first travel to Limsa (etc), transfer worlds, and then go back to Sharlayan.
It's impractical, and thus the likes of Limsa becomes the 'main hangout city' because that's where our free travel point is set.

It's a shame to have these wonderful new city hubs every new expansion that seem to almost never get used, outside of hastily popping in to spend tomes and nuts.