I think quest NPCs will be a very good thing on nations.
basically how they would work is simple: mayors and leaders from nation can spawn NPCs and plant custom quests inside them, and other residents will be able to talk to npc and accept mission, after completing mission, resident will be rewarded with cash, this way towns can be more filled and customized by players.
this npcs of course will have limit and they will be despawned in siege zones, respawning after siege zone goes off.
this way mayors and leaders can give tasks to their people without need to be online. and it makes towns alot more wonderful