About the markets, the word capacity is incorrect, it should not have been there. Markets don't reduce your capacity at all and just cost 10 Wood and 10 Pottery. I will add a details to it. Furthermore, you should have enough production for the extra upkeep to buy one. As said, I will add info in a future release.
I balanced the upgrade/upkeep cycle a couple of times, and I see your point. I will look into it whether I can change this, but it is actually tougher than you might think, as I don't want a severe penalty to happiness when you are upgrading (one version had that: upgrade anything and drop to 0% happiness for upkeep). So, I will take note of this and see if I can slightly change the priorities, but I don't want to change too much in this area (as other deadlocks can arise)
Thanks for the compliment. I hope you recommend the game to others.
Ps. for mobile the android version is the same as this version (but with an optional speedup function)