What if LA gets totally destroyed and it becomes an exploreable area, and they make new LA on that hidden zone between current LA and Kessex. (map: http://i1146.photobucket.com/albums/o527/carralpha/GW2mapannotated.png)
That area is much smaller but this way they can keep all the TP, Banks, Crafting, really close to each other, and maybe not all of the current LA is lost but some of it is.
I actually considered this. I'd still put it under the realm of "highly unrealistic", but it would be a way for Anet to say, "look, we've changed, it's not the same main city!" They could then use that to tout how much the game has changed and incentivize people to come back and check it out.