As I continue to ponder the problems of scale, here's what I'm currently looking at.
36 mile hexes must be rejected.
72 mile hexes must be minimum, but a larger size is preferred.
72 mile hexes (flat to flat) equates to 62.352 square miles.
If I am to attain a 15,000 man army for the Grand Duchy of Khornwallistein, the current largest nation of 85 hexes giving us a land area of 5300 square miles, I'll need a base population of 1,500,000 people.
This means that the population density must be slightly over 283 people per square mile.
This is just far too dense, especially since this does not take into consideration areas that are heavily forested or mountainous or otherwise uninhabitable, meaning the actual density of habitable space will be over 500.
This would place it at 70 out of 246 countries and dependent territories of our own world.
This is impractical at best.
The concept of the ImagiNations here are that they are independently capable of recruiting and maintaining reasonable armies without crippling their economies, standards of living, or growth rates.
Now, I could probably fudge things a little, perhaps accept a 5% ratio of manpower to total population. In this case, the population of Khornwallistein could be reduced to 300,000, giving a population density of 56.6; a perfectly reasonable number.
However, there still remains a problem. If the army meets with disaster, the economy of the country will take a significant hit as it cannot then recruit enough replacements without pulling able bodies out of necessary industries, especially food production and military manufacturing.
Also, as Khornwallistein is the largest nation, I am going to need to look at the smaller nations.
Saving the trouble of posting all of the calculations, this means that the Free City of Passant (which is more than just the city) can support a bit more than 1920 men. The Earldom of Mysterae can support 3352. The Nurglundian Marches would be able to field an army of 8470, with the Princedom of Slaavia mustering another 7587. Tzeeberg's army comes in at 9880.
It may be that I need to adjust the map slightly, to give the Nurglundians and Slaavians more land area, and thus greater populations to recruit from, or develop a reason for a much greater population density than "normal." As these two nations are the primary antagonists towards Khornwallistein, having them weaker militarily just does not make a lot of sense to me.If they were each capable of fielding armies roughly equal to Khornwallistein, then conflicts would appear reasonable instead of like small dogs yapping at big dogs.