I take umbrage with this:
Low Position of Women - The most important occupations are going to be
miners, metalworkers and warriors, all jobs which require great
physical strength and will favour men. So it is likely that the
culture that develops here will be stereotypically masculine. Combined
with the high level of social stratification, and there's a good
chance this society might have polygamy among the upper classes.
You're missing something vital. Trade. It's nice that there's mining and the mining is important. It's nice that fighting is important. (although if it's a narrow straight like you say, archers would likely be as valued as on the ground fighters and women can certainly do that.)
But if all the men are fighting and mining, who is left to do the dealing? And with as much trade as they will have to do, I'd guess that's the women. Doesn't take physical strength, just shrewdness and the ability to talk.
So I would argue that a female merchant class is definitely in the cards here. Stretch this even further and the effect might actually be the OPPOSITE of what you think it will be. Women end up owning and ruling because they don't have to do the physical labor. Send your daughter or wife to make your deals because you have to be there at the mines managing your men.
That you've chosen the Renaissance as your model is especially interesting because this is the era of the rise of the merchant class. And there were certainly a lot of women who took advantage of this.
When you say "polygamy" I assume you mean one man and several women in a marriage. It can work the other way as well. But let's look at the way you likely are--one man, many women.
Polygamy works best if instability is introduced into the system. As in, for instance, there are much fewer men than women, or not enough men. In this case polygamy can help keep population numbers up. Polygamists/polygamous societies have a high mortality rate. THERE'S A REASON FOR THE CORRELATION. It's not that polygamy CAUSES a high mortality rate. It's that it's advantageous for humans to be polygamous when there's already a high mortality rate, thus the correlation. Pretty much if things are out of balance ratio-wise, or your death rate spikes, guess what, monogamy loses many of its advantages.
So, if there are, say, a lot mining accidents, and dead men, this could work. But that would be a lower class job. You're specifically tying monogamy to the upper classes. It would help things if the men did die with frequency even in the upper classes. This would mean women survived them, and if they remarried, they would likely come with $$ from the previous marriage (divided amongst the wives and children though it may be). Lines of succession and power, problematically can become really really muddied when everyone in the upper class practices polygamy. Civil war can be more likely because of this. A household full of wives and their children all of whom want a piece of the pie? You've got plenty of plot to work with! Even if the ladies are low status, you can bet they will work for their kids. (Whatever rules you have in place, forget about them. In this situation many dynasties have fallen because of competing wives.)
However, socially, if your ratio is more balanced, there are problems that develop, some of which might be advantages in your model. (Less births means less people to feed).
- A large household can result in older siblings being responsible for
younger ones, and the older siblings might be expected to earn for
the family, resulting in later marriage and less kids overall in the
population.
- The birthrate, overall, can also be lower, not higher than with monogamous models for other reasons as well. Studies of polygamy and birthrates have found that the more wives a husband has, the less children PER wife. It seems like they have more kids because, well...they are all in one place and from one dude. Some are prolific no matter how many wives they have, but the numbers overall seem to indicate that each woman has less children compared to a mono model
- Some men have bad genes. And if they have a defect, and then go on to have a dozen kids, that defect is spread far and wide.
- Lots of men without wives, or they have to compete more in order to get any women at all because a few men are hogging all the women. Men, in this case will not settle down because they don't actually have the option to. One powerful man marrying a dozen wives means that, if the gender population is equal, that a dozen men won't be able to marry those women.
- Less genetic diversity, more birth defects, eventually.
Mercentile / Outward looking - If the population is going to grow past a low level, they will need to import food from other countries.
The effect of this is going to create a really diverse place. Your society is going to be much more than just the natives, there's going to be imports from far and wide, not just of goods but of people. And those people will import customs as well. Since they are outward looking, your natives are going to have to be tolerant of most outsiders, and welcome them in. After all, the well-being of the community depends on those imports. (They'll become markedly LESS tolerant of any of these immigrants take mining jobs, which, if a wealthy mine owner has a labor shortage, well...they just might hire/import workers). There will be wealthy foreign merchants, some of whom might stay enough generations to be seen as natives, but still have connections to outside trade.
Stratified - Power will be concentrated in the hands of a small elite who own the mines and the smelters, plus those with good trade connections. These peoole will be able to hoard food to get through any disruptions in trade, when others will go hungry.
Yes and no, because of your first point about the mercantile/outward looking aspect. Concentration of power in the hands of an elite--this has always been the case in most societies. But Renaissance? That's when things shifted. There were princes, elites, uber merchants and bankers who had the most power, but there was also a new society emerging. A definite middle class of merchants. Power can still be stratified, the elites can still hoard, but don't underestimate the middle class in this scenario. Plenty of entrepreneurs will be working. Also don't underestimate the lower classes...Medieval and Renaissance times has had plenty of peasant's revolts. If it's obvious that the elites are hoarding food, you WILL have a riot on your hands, guaranteed. This will be especially true if you stick with having NO middle class at all--(no shopkeepers and the like) because the lower strata will have NOTHING TO LOSE.
Militaristic - Survival will depend on protecting trade routes against pirates and bandits. This will require people to fight.
You really won't need that many people to do this. And I don't think it will be military/government oriented in nature. Instead it will likely be mercenary oriented, or specific to merchants-- you hire people to protect your wagon train. And maybe you pay a percentage to use a particular road and there's general soldiers patrolling. I would expect that a very powerful merchant would have their own forces. Perhaps each one would. Maybe each would reach an agreement about what part of the trade route they protect. My point is that it won't be organized as one government assigning guards to trade routes. Take a look at Renaissance Italy--the Medici, the Borgia--they had their own forces.
ROLE OF MINERS AND SOLDIERS
A soldier/mercenary would be probably lower middle class, if not lower class. They'd be provided for by the merchants and get money besides, but they work for the elite. It doesn't make them elite to be one. An occupation can be important without it being high paying. Miners can be important, but if there's a lot of them--if you were a mine owner you would you want to pay them any more than you had to? Nope. You'd want to maximize profits. Just because their society is dependant on these folks doesn't mean they have prestige. There are plenty of jobs currently that society depends on which don't, and the same was true in the Renaissance.