Heat System for Underground/Illegal Locations
It makes sense for the illegal contacts & locations to move often to evade law enforcement. Maybe this is already being taken into account but I suggest a sort of background points system based on how much use they are getting, crimes committed at the spot, & so on. This would be a hidden value but would be more dynamic than simply moving them all periodically. I think this would encourage better RP at those locations & maybe make people less likely to share info with strangers on day one.
Possible addition: Temporary time-outs for locations generated by PD. If I do something that draws police to the location I would expect business to stop while they wait for things to cool off. IDK if this is possible but as a sort of automated Not Valuing Freedom thing, loud violent crimes triggering a 20 minute cool down for any NPC criminal activity in the immediate area could be interesting.