Catching wanted NPC criminals is interesting idea for a repeatable job imho, but I don't think it should be every "raider" mob. Instead of trying to track and catch a specific NPC you would have grinding encounters.
Just for a side info even slavers can't tie up raiders. The critters that can be made slaves are limited.Though we have this faction in game called rangers how about making them a faction that can be joined then give its member the opportunity to hunt down certain slavers and criminals they could be named NPCs and those who are belonging to ranger faction can tie them up bring em to a ranger outpost where they get shot in the head.