DreadPirateMurphy
Explorer
Even in the modern day, cities require massive amounts of farmland. The 2% of the population in agriculture is only due to automation. The hard part in a real Points-of-Light campaign would be protecting enough land to serve the population. That's going to keep population relatively small unless you have some kind of magic in play.
Keep in mind that a city doesn't have to have farmland right outside. Rome used to ship grain from Egypt. It does presume an ability to protect shipments of food, however. Maybe a large city survives via trade portals or teleportation?
Apart from that, pretty much every community is going to be very vulnerable. There is only so much you can do to defend a small population, and you're not going to have the depth of reserves that a larger empire would. Expect a degree of xenophobia and paranoia. Justice is likely to be harsh, vigilante, or both.
Keep in mind that a city doesn't have to have farmland right outside. Rome used to ship grain from Egypt. It does presume an ability to protect shipments of food, however. Maybe a large city survives via trade portals or teleportation?
Apart from that, pretty much every community is going to be very vulnerable. There is only so much you can do to defend a small population, and you're not going to have the depth of reserves that a larger empire would. Expect a degree of xenophobia and paranoia. Justice is likely to be harsh, vigilante, or both.