I decided to set the fort as built by default. Since this building is almost always necessary, but at the same time slows down the pace (typical development to a castle without a fort in the first week would take as much as 3 days of construction out of 7).
In villages (secondary towns), the fort is not built (but the tavern and tier-1 building are, as in the main town). This means that when capturing a village, we will have to invest in building a fort in order to be able to actively produce creatures (without a fort, only magical creatures and tier-1 can be built, which is already built).
If a fort is built in the main town, will this determine the basic color (grade)? I really liked the idea of choosing a basic grade (color).
For Humans, there are 4 options with militia and archers:
1) an arrow from militia to archers
2) an arrow from militia to archers, but without an arrow from the fort to archers
3) an arrow from militia to the fort
4) no arrows from militia
For the Dungeon, I'm still thinking about what to do with the growth rates of scouts and beasts:
1) do nothing
2) increase the growth rate of scouts from 5-15 to 6-18 (max 4500)
3) increase the growth rate of beasts from 4-12 to 5-15 (max 6000)
4) increase the growth rate of scouts and beasts
It is also questionable whether a requirement for the shipyard from the castle should be set, or whether the shipyard should be independent (then the shipyard would theoretically be available in any village without a fort, provided that the required town level is reached).
The training limit will be increased from 8 to 10 creatures per week (while training remains free).