Personnally, i don't think citizenship is a good thing to make the town apolitic.
You could have struggle for leadership, betrayal, spies, gangwar to hold the cave and other stuff.
As i see it :
- Free access to upperground area, with a lot of random spawn point. So there is no camping abuse as you don't know where bluesuits gonna spawn.
- The two access to the underground are guarded by npc who attack those who attack others. No reinforcement, no superguards, but you can see them from afar. So if you don't see them it means the entrances are not safe.
- Generic glowing ghouls during night, who help the guards. (more falloutish)
- When you goes underground, there are doors that you must pass to enter the cave itself. To pass the door, you must give your weapons to the guards. (they will disapear, forever) If you kill the guard, you can't pass the door. (those inside could leave by a red exit)
- If you attack someone inside, you'll be killed and loose 500 reputation. You go under 1000 you will be shot on sight. So there will be no unarmed gang rush. (or less)
- No citizenship, no computer, no faction, no stuff, no ressources, no traders, no containers, no idolated reputation for players. Maybe some homesteader or generic quest guys. So there will be no struggle for the leadership of this place.
- Mini questmap around the ghost farm. (quest given from inside the cave. the reward are never weapons)