So I had the idea while looking at servers to join and seeing all the differing structure destruction times. Make unvisited structures have a chance of being taken over by aliens and becoming a new POI. This could include keeping whatever is currently inside as potential prize loot or wiping out the contents of the containers and filling them with whatever randomly generated loot per tables. Maybe the aliens would fortify their new buildings with more or better turrets or drones in addition...
Player Made POIs
Player Made POIs