Thanks for the dev diary!
I'm slightly dissapointed in the new province policy because it's fairly shallow. I would love to see more city specializations so that certain cities have more importance and I feel like the new provincial policies don't do that well enough.
My suggestion would be a city focus policy similar to provincial policies but for cities instead. Obviously there should be a limit to reduce micromanagement (such as limited to finesse by governor i.e 5 finesse=5 city focuses in region).
Example "city focuses" could be:
Production:
-Provides x% of slave growth of other cities in province to this city
-reduces slaves required for surplus by x
-% chance of captured slaves being sent to this city
Manpower:
-Provides x% of freeman growth of other cities in province to this city
-reduces training time
-increases manpower recovery rate of city
Citizen:
-Provides x% of citizen growth of other cities in province to this city
Tribesman Enclave (civilized nations only):
-%chance to move tribesman to this city
-Lowers civilization level of city
Holding Expansion:
-Governor with holding in city can set this focus
-Provides boost in wealth production of holding to governor
The over goal would be to make some cities more valuable and strategic and not simply provincial capitals although that is cool as well.