Alex, obviously a poor choice of words on my part as I never meant to imply you were lacking in intelligence, and by “here” I’m defiently refering to what is written, not to what you may or may not know beyond the page. So my apologies.
Having said that, settlement pattern, generally, and particularly in the north atlantic during the viking age expansion, is my sthick as a scholar. I can, pretty well deomonstrate, that population density is not a measure of productivity or carrying capacity, in any society, pre-modern or not, but doing so, as I’m sure you can imagine, would take a heck of a lot more space and effort than I have here. The short argument is that population density is primarily a function of social organization and cultural norms. Brian K Roberts Landscapes of Settlement: Prehistory to the Present
might be worth a look for you.
I do realize its a game your after in the end though so your point about what it is you want to simulate is well taken. Population density and available wealth is tied to the value of labor, generally, so that if you set the wages being paid you might be able to work out a ratio or range for the other two. Food for thought anyway.