Current state of bread production chain is dissapointing.
Lets compare it to other food production chains.
Meat/fish. At the early stages we have only hunters and fishers. Their avarage productivity including smokers is ~150 per year per worker.
Later on with barns we have 1364 per full barn, so ~200 (adjusted for the smokers). I assume milk is a compensation for winter feed, so I don’t count that.
Fruit and berries. Without preservist we have very high output for foragers and arborists ~400. But it is compensated with fast spoilage. With preservists it drops to ~200. So almost the same as meat production.
Beans and vegetables. One farmer can harvest up to 500 food per crop. And it is ready to eat with 1 year spoilage period. Very good. Field maitenance and preparation need to assign additional workers, but still avarage output 300+.
Bread. Now we have bread with chain “wheat-flour-bread”. Wheat output the same as beans and vegies let’s take 500 at best. Then we need to produce flour, and it is another 500 per worker per year. But including farmer there are two workers already, so it is 250 per worker per year. Then we need to bake bread, and baker’s productivity is another 500 per worker per year. So to produce 500 units of bread we need 3 workers. As a result we have output ~166. Not so bad you might say. It is even slighlty higher than hunters and fishers.
But! The bottleneck of this chain are mills. They are way to expensive - heavy tools, flax, tons of resources! And to provide one bakery with flour you going to need at least two(!!) mills. Another point is that bread spoils very fast. It is justified but it need to be compensated in some way.
I’d suggest doubling the mill’s output so we can have 1 mill per bakery at least. This will increase bread output to ~200 (keeping the same number of workers in mill - 2).
And another important suggestion: reduce the flour storage capacity to 100 units instead of 200. Flour is stored there for too long, and with multiple mills, that number can reach into the thousands - laborers can’t move all that flour closer to the bakery, and we need the bakery in a residential area and the mill far away. Therefore, bakers usually have to walk to the mill, which reduces their productivity, or the player has to build up a huge stockpile of flour before starting to bake bread.
Thus, the per worker per year output for bread is valid under very optimized logistics, whereas normally they would be significantly lower due to high storage capacity at the mill, even less than for hunters/fishers!
UPD. In addition to the last thesis - producing 500 units of bread, with all that walking done by bakers, it takes 4 workers - 1 farmer, 1 miller and 2 bakers (reduced output of a bakery is ~1000 per year instead of ~2000). So avarage output will be only 125 per worker per year