I like
this post. ...I hope I have the right link, that's the one with the Alpha Pig, right?
How 'bout a claim flag instead enables a guard spawner? You could add a friend's list thing to let dudes beside you work the area. Make it expensive (maybe an iron chest with a gold
block, not bar, inside - represents a guard locker and his pay or something), that made a friendly/neutral mob that attacks people if they see them attacking something on the claim?
Making NPCs would actually be pretty rad in general. Could
over-complicate the guard idea by making it divisible into patrol guards, sentries, and response guards or something. Sentries have a set spot they stand at and a really long sight range, patrols walk around the claim, alone, and response ones sit on their spawn until one of the other two see some mischief - so they all come in one big wave, unlike the lone patrols. Maybe also start them unarmed, and have their spawn have an equipment inventory - armor and a single weapon slot. You'd have to make their equipment, but you could arm them how you wanted - entirely bow patrols (ignoring arrows, cuz' that's lame), mixed patrols, whatever. Also maybe further increase cost by requiring the player to rebuy the guard if it dies, and eliminating the guard's equipment on death - add a slot for a gold bar in the spawn thing, maybe it could fit a stack, so you don't have to micromanage - or put the stacks in the claim flag.
"Stop right there, criminal scum"
Possibly also a worker guy spawn to auto-repair your claim by tracking and referencing how you build/leave the place and your changes.
I mean, we're gonna need super-AI for NPC settlements anyway, right?