I dont know how VGN is going to built but I wanted to add some thoughts that "may" help or just give you some food for thought:
In the early days of Victoria beta one of the places I personally feel that the game laid the foundations for future failure was the approach to population break out. In many ways the POPs approach was fantastic, I really liked it, but there was one major issue:
Farmers globally were classified the same. Rather than have different types of farmers there was one universal category. Even if you go to India or Africa today you can see that many of these people are still not equal in development culturally to farmers in Western Europe in 1850. Yet, Victoria made all these folks the same.
The result was that the main base line population (farmers) in the USA, UK and Netherlands was the same as the main base line population of most of Africa, India and China.
The outcome of this was that it was, of course, just as easy to develop rural indian farmers as it was to develop farmers in Surrey Southern England. So we had huge modern armies being raised in india along side modern industry which they still struggle with in certain rural Indian areas today.
The overall effect was that the game needed to continually draw up "hard rules" in new patches to get around the model inconsistencies that were creating very odd results. Of course all they were doing at this point was band-aiding a broken system, and band-aid's dont stay on long before another is required.
Now, I am not saying this was the only problem with the game. Afterall there were some major other issues even at this early beta stage such as Navies were going to be meaningless except to transport troops! But it was one of those core problems.
I believe that hard-fixing/ band-aiding after the problem event causes alot of problems. Better to get the model right at the begining, and keep it simple, working is always better than not working right?
Anyway, like I said at the begining, there may well not be any relevance to the current work; but maybe it gives you something else to consider as you develop what I hoping is going to be a great game.
Good luck