We can't force the populations of the current feeders along with us.
If a delegate is popular many (probably a majority) would follow her.
It was just a thought anyway. Having a big region would be interesting, and such a region would have much power in the nationstates universe, but I don't know if it will ever happen, at least not soon.
*waves at Andromeda*
The problem is that most nations who endorse a delegate only endorse them because 1) they're there, and 2) they asked for an endorsement/gave one out.
No one except the people who really know the player behind the nation (from interacting on the forums) would follow a delegate out of region. Most people hardly notice, let alone care, when the delegate changes. Would you have followed a delegate out of The East Pacific, if he had asked?
Out of the thousands of nations in the Pacifics, I would say at least half are puppets or only occasional nations, which will Cease To Exist in a matter of months. The feeder populations only remain so large because all nations of this sort get dropped into these regions.
If a feeder delegate were to leave and found a new region, they would no longer get these "free" nations to join their region - all new nations would continue to be dropped into the old Pacifics. The delegate of the new region would then have to recruit from the Pacific they had just left in order to gain new members. They would be in the same position as any other User Created Region.
The feeders have the distinct advantage of having the first shot at recruiting new members to join their forum communities, which is the only way things are accomplished and more fun is had in NS than is available through game code. In a way, your suggestion is like asking all the oil-producing nations of the Middle East to pick up shop and move to some previously uninhabited bit of land. It would be a mistake to think that those nations would continue to be as powerful as they had been before, because their power is derived from their control of resources which are tied to their location. In RL, those resources are oil fields. In NS, those resources are the game code mechanics which drop new nations into the region.
The best you can hope for is to create a cooperative overarching structure like OPAC. That has been attempted in the past in NS, but tensions and a certain element of self-centeredness between the feeders keep such cooperative structures from having great effect on... well, anything.
(The Azure Alliance - is that still in play, or no?)