Don't know if this has been requested before but I've never seen a post nuclear war mod done before. I always thought it would be cool to watch a small settlement or town form from around the hollowed out ruins of giant skyscrapers.
For instance having little scrap shacks and junk buildings for low income, medium income being structures built from or incorperated into the ruins of pre-nuclear war structures, (like having a market place in the middle of twisted metal remains of a skyscraper) high wealth being completely new structures all together. Dirt and gravel roads, small and expensive water sources, small wind powered generators, volunteer fire stations, and hired gaurd stations (to replace police). For education maybe have a settlement elder gathering (for a school), pre-war book collection (for library), trinket house (for a museum), and ruins scavenger guild (for higher education).