Prisons:
A prison on one of the islands that you get sent to if you kill a bunch of town guards or players in a guarded town and in turn are killed in the process. Instead of spawning in one of the start locations as a blueshirt with low health, you spawn at the prison as a blueshirt or in black and white prison suit.
If that is even possible to program, as in only those who actually did the shooting get sent there and not and innocent bystander who got caught up in the crossfire.
If it isn’t possible or just too much of a pain in the ass to do, then it could be a place that the game administrators send players for breaking rules or if the player wants to go there. Maybe there could be quests set in that if it you fail you could end up at the prison, a nice pay off if done without getting caught.
You have to be there actually logged in for X amount of time before you are let out. You can reduce that time by mining iron ore in the prison yard or cutting wood and so on. You could get a prison tattoo as well. Have an NPC there that could teach you a support perk that improves knife attacks.
If your group has a Vertibird they can fly to the island and try and get you out. But if they are killed in the fight with the guards, they will also end up as prisoners. Preferably it would be a small island so the only place to land would in at the prison location, outside of the gate, so you would have to be mindful of other players getting out and taking your only way off the island.
But yeah that could cause problems. “Help we got stuck on the island became some ass sneaked in and took our bird.”
Maybe there could be a boat or some other water craft to get off the island so players can if they figure out a way to escape can leave the island. Such as there could be items throughout the place that if found could make dynamite which could then be used to blast a hole in the wall...
Alternatively it could just be out in the desert some place with a moat around it like the Gun Runner’s place.
It could be run by the NCR or San Francisco or they could both have a prison.
I am aware this would be a lot of work and it might not be much of a payoff, anyways just throwing ideas out there.