Another problem is implementation. The way described, each cargo item would have to have a value assigned to it that it was stolen from [x,x], or that it was stolen at all. Then the NPC would have to go through each item, scanning for a "stolen" value. Which wouldnt be that bad, as search funtions dont take up much CPU. Problem comes in when there's multiple players in one system. Then the NPC would have to diffrentiate between high and low priority, which would just cause a strain on the NPC, and you would most likely have him parked, turning this way and that.