These will not be terribly populated factions.  It's a situation that is basically meant to be a demonic Switzerland as one way to word it.  A large city-state here should only have 100,000 people.  

Or maybe more since having a dense population, high tech and a small but highly vertical and mountainous space is the name of the game here

Much of the action is underground after all.  Everyone is based in purgatory, but colonizing outside purgatory I am fine with just don't make any land masses as large as purgatory.  Any historic urbanization behind outposts from centuries ago will be examined when brought up.  But the focus of the NRP is on neotribal politics in a giant mountain with lots of underground zones and strange locales.