I'm not sure how to say it but anyway..
I don't know how stable the civs in genaral should be but.. I started a game with Genoa and not once (after the first 10 turns) has my stability been at 10 or higher, usually around -2/+3 constantly fighting to keep it at least 0 or a positive number.
Although I built stability buildings with a very high priority, I rarely build that many Castles (every city received all stability buildings ultimately) and that without really bothering about stability, I build courthouses because of the corps and most other stuff for all kinds of reasons. I'm not even sure if I bothered with the 'Night Watch' with Portugal and certainly not all cities received castles.
The game I played with Portugal was much much more stable. Usually at around +10, at the last save point +18 and I am actively waging war against France (winning back those territories of my vassal Spain after they respawned xD)
or maybe I shouldn't have founded 5 corps.. you do get a stability hit -2 each time you found one, but that was something I just had to do
I'll just post the numbers from the civics screen.
Both civs running the same civics (Lim. Monarchy, Bureaucracy, Appr./Guilds Org. Religion, Imperialism) pretty much established the civs in the same order too.
1. switch manorialism/feudal monarchy(genoa), manorialism/militarism (portugal)
2. switch bureau. / org. rel
3. switch appr./guilds
4. switch lim. mon/imperialism
Portugal: 11 Cities, +18 very stable in 1772, Hanseatic League and Bank of St. George (built all colonies)
cities: 7/6
civics: -1/-1
economy: -5/7
expansion: 13/-8
Genoa: 10 Cities, +4 stable in 1566, 5 Corps (Hanse, Hospitaller, Medici, St. George, Augsburg Fam.)
cities: 8/-2
civics: -10/1
economy: -3/5
expansion: 11/-4
the stability figures are similar for both civs, except for the civics part as I just noticed.
Any ideas what I did wrong with Genoa? Besides taking Napoli which seems to have had the hardest impact on stability which I never got a grip on after that. Or still running Bureaucracy? Or razing those 2 annoying indie cites in greece?.. but they had to go. DOW on indies every time I passed through the area and the indie cities in sicily and north africa retaliated on my seafood resources and ships. That just had to stop.
So.. to get to the point, I really like the idea of a small stability boost for a city if you hold it long enough, but that might be way too much for other civs..
I just noticed one of these 'tip of the days' during game load..
Merchant Republic is great for peaceful small empires (something like that)
France in my latest Genoa game.. solid/very solid with 15 cities in France/northern Spain
running...
Merchant Republic, Bureaucracy, Apprenticeship, Manorialism, Imperialism
well with those civics and that 'Empire' I certainly wouldn't expect solid/very solid
with the proposed stability boost they would be 'rock solid'?
From that I guess my concerns about Bureaucracy possibly ruining my stability as Genoa were unwarranted.
And btw the game with Genoa was a UHV victory in 1640 so that's working fine

But getting open borders with 10 civs in 1640 wasn't easy since there were only maybe 12-13 civs around, luckily Bulgaria respawned early 1600's. And I finally did get Mercs with Genoa but only 2 'Condotorri' in the entire game, even founded Zurich (named Cumae) to have a settlement in Swabia for Swiss Pikemen, but didn't get any. Especially since it's the UP of Genoa (cheaper mercs). But all in all the new merc thing seems nice. But I'm not so sure about the part of only being able to hire certain mercs when you have a city in the province.