i love this idea!
reminds me of the city sieges in WAR.
what could be done instead though rather than have the "sanctuary hub" violated, as many fear would inflict lag and other issues/annoyances(even though a separate instance is suggested). would be to have that battle/invasion in a different location alltogether.
maybe its one of the star-destroyers that is being attacked, or maybe another fleet staion nearby, or for the sake of it bing THE station say its the station itself.
point would be that instead of switching to an instance on the fleet itself, which could cause lag etc, youd get get a message with the offer to "repel the invaders"(port to location and battle) or "decline"(stay where you are currently located)
it would be even more awesome if there were some space pvp involved in this. granted i never liked the implementation of galactic starfighter since it was far from what i was hoping it to be in flight combat. but this could be an excellent time to tweak that part of the game aswell.
(there so much id want to add to this, but its 6 in the morning and im in no mood to write a book >.<)