I just want to pause and take stock of the tech levels so far.
Early in this process, I had a faction of respondents who suggested that I should subdivide those first tech 5 regions into multiple technologies - to reflect that a single region, especially one as large as the Lungos Nad example I gave, should be more than one technology. By now, with hundreds of regions now accounted for, ranging in tech levels from 5 to 9, I wonder if it can be seen now why I wouldn't want to subdivide this issue still further into sub-regions (and presumably, sub-sub-regions . . . oh, where would it end?)
I have about 33 remaining technologies to spread among the remaining 9 tech levels - though I can improve that by updating various lower technologies (separating 'agriculture' from 'irrigated agriculture', for example) and adding in things associated with magic - say, the creation of magic items.
I've been thinking about the relationship between tech levels and the percentage of leveled persons, as well. While there are 619 regions with a tech level between 10 and 14, there are only 96 of 15 and above - and I like the idea that most of the residents of those higher tech levels would be actually leveled. There are only 10 entities with an 18 technology, and all of those are free cities in either Germany or Italy, being 1/10th of a hex in size with 99,000 or more in population. Why not make a completely leveled population as a distinctive feature of those places?
That would certainly give the players pause before entering such places, putting them somewhat on edge. And on edge is where I like my players to live.
As technologies climb, it only follows that the level of civilization would become less comfortable for adventuring. Population and densities climb, there are more potential enemies around, loaded up with weapons and magic . . . it is only natural that if the players start something, there are going to be plenty of personages around to put the hammer down.
In many ways, I can see the players preferring to retreat to the lower tech levels, where they can reasonably count on being the toughest fish in the pond, free to operate as they like without a lot of intrigue, accountability or social mores. Then again, some players like that sort of thing - and since my world is a buffet, the fish can swim into whatever troubles personally suit them.
All I want is a much clearer glass to demonstrate what's going on where, so that the players can fine-tune their own experience to the sort of environment in which they'd like to play - with the freedom to drift from one end of the scale to the other without my having to do it for them. It really makes a mess when the world shifts radically from one extreme to the other, attempting to keep every kind of campaign in the same space.
Letting the players do that, taking up their stuff and moving when it suits them, gives them greater power to create a narrative that works their way. Me, I'm happy to manage whatever campaign they like.
This is perhaps a major reason why I don't get bored with 'one' campaign after ten years - because I'm not running a heterogeneous world. I'm running a multi-world, with as many variations all in one place as a score of DMs running a very fixed and narrow concept-driven campaign.