Definitely some good ideas.
I’m not sure that it is really feasible, for most of the buildings, to say that you need X for a Y population. I feel like too much is interconnected.
Think of the food industry. How many hunters should I have? Well, having 20 hunters won’t do you any good if there is insufficient game to hunt nearby. Then again, once you have farms, with a ready supply of cattle to butcher, I’d only keep enough hunters to round out the protein and go after bears and boars. Maybe your village is right next to a large lake, and your fish supply is overwhelming. That can cut down on how many hunters you need. Foragers too can require you to have fewer hunters. As well as fields.
What about wagons? If your town is pretty compact you would need noticeably less than a village that is spread way out, even with fewer villagers. How do you translate that into “you need X for Y”?
Weapons/arrows? How many hunters do you have? Are you raided often, and by how many? Lots of wild boars and bears in the area? They would all affect what you need to produce.
Industrial buildings? Is 1 glass blower sufficient for a Y population? Having preservists will increase your need for glass, but only if you have sufficient fruit and veggies to preserve. So how many fruit trees and foragers with access to berries do you have?
There are some buildings that probably could have a small range for answering “X for Y”. Cobblers. Everyone needs shoes. Although I don’t know if the game takes into account how far you travel for work with regards to shoe life. If so, then that number would vary quite a bit depending on how your town is set up. Chandlers and Soap Makers. I feel those are independent enough that you could do “X for Y”.
Just thought about the Night Soil Collectors. It’s not just how large your population is, but how far they have to travel to get to the homes. I was keeping my compost bins out near the fields, to keep them from negatively affecting homes. I found that I was having waste build up in homes because it took forever for my collectors to walk back and forth. I ended up increasing the number of Night Soil Collectors.
Sorry for going on so long with this. I think how many you need of a specific building is going to be unique for your village, and part of the challenge ( and fun ).