What would happen to EVE if PVE and PVP were indistinguishable? Imagine fighting an incursion, but the incursion is made up of other players. Sansha (or other faction) rewards its champions with shiny loot or LP for taking a system, Concord (or Gallente, etc) rewards those who answer the call to defend similarly. While we're talking hypotheticals, what if a Gallente force could take Jita?
I know, it sounds like faction warfare, but let’s take it a step further. What if all missions affected NPC sovereignty? Your L4 agent might, for instance, send you to the front lines where you would be auto-fleeted with a small gang trying to take out another small gang. And maybe - just maybe, rats fill out the ranks. If you succeed, your agent gets to keep his office in Dodixie. If you fail, you might see an exodus of Fed Navy officials fleeing the stations.
If you are a successful fighter, Amarr might post a bounty on your head making you a more attractive target the next time around. If your bounty is high enough, you might get shot if you show your ugly mug in Amarr space (and not by faction police!).
What about null sec dwellers? How do they get a piece of the action? Alliance control of hi sec! You read it here first! Hi sec would remain NRDS. Of course, if you're going to try to take a piece of hi sec away from Caldari, you'd better be prepared to defend it! Why would an alliance want to take a hi sec constellation? Tax revenue generated by players AND NPCs. Fed Navy might pay an alliance to host their diplomats (allowing mission runners to do their thing).
Security status goes away. Your legal authority to be in a particular area depends on who controls the system and your standings with them. You increase your standings by fighting your host's enemies; your status decreases if you fight with the enemy.
No more static storylines! Minmatar will have the potential of winning Amarr space. The Gallente-Minmatar alliance is not a forgone conclusion. Caldari might find they have more in common with Gallente when faced with hostile Amarr. A new AI might guide the story, but the players will control the outcome.
Yeah, just daydreaming here. I think this might be one of those Jesus expansion thingies.
EDIOT: Almost forgot...Sovereignty goes to the occupying force. No nation in the world is established by planting a flag in the middle of the cornfield (desert, playa, savanah). Also Sovereignty isn't suddenly re-assigned when that flag with its stupid tank is finally taken down. Sovereignty is held by the people who occupy the land ....erm solar system.