From what I saw, you get 2% unrest in all your cities for each city built. So if you have 5 cities, all your 5 cities will get 10% unrest penalty from number of cities.

That being said, there are buildings, and upgrades that eliminate said penalty (number of cities penalty specifically) although they work only on 1 specific city. Also, there are fort upgrades for level 4 and 5 forts that give empire wide unrest reduction -10% and -30% which basically gives you a good reason to make more then one fort in order to counter this unrest penalty. Basically, for each 4 cities you need fifth lvl 4 fort in order to keep unrest at the same level.

Basically the system is currently pointless and can be completely countered allowing unlimited cities so long as you build the "correct" cities with the "correct" upgrades.

Hence "correct" cities and "correct" upgrades. You have to build the right balance of towns and forts, towns to increase food in all cities to grow them rapidly, and forts to erase unrest.

It doesn't have much impact either way, 30% unrest is pretty much nominal if you have 20+ cities. I think some people are misunderstanding the unrest mechanic and trying to avoid all unrest at all cost, when really it has very little impact until it starts getting into the 80%+ range. 20 cities working at 70% efficiency is a hell of a lot better than 5 cities working at 100% or 10 cities working at 90%. Heck I take rebels and cruel on my custom factions and sov because unrest means so little right now.

I think it needs to be boosted to like 5% unrest per city, with the empire wide -unrest% upgrades on forts being changed into something else. All the current system does now is handicap the AI who doesn't know to go for X amount of forts with specific upgrades. So the "correct" strategy for the player right now is to city spam and overwhelm the AI, but at least the current mechanic allows us to build fewer cities ourselves if we want and still have some challenge (so I don't want to see the system reverted to what it was before, it's an improvement, just not far enough).

This is all assuming it maintains the 2% unrest per city later on, I refuse to build lots of cities so I don't know if perhaps Daynarr is mistaken and it scales higher with more cities.

I'll take a look if there is increase in penalties on larger number of cities. In my first game I had 16 before the end, but didn't check specifically if penalty was 32% or larger. Doubt it, but you never know.

I don't see what would removing fortress bonuses accomplish other then force EVERYONE to have few cities at most or have their production completely halted. From what I saw, the whole mechanic is geared toward slowing down expansion and penalizing pioneer spam at the start of the game. Also, there is population cost for pioneers so it limits the spam even further.

I don't really think that example of 20 cities really works that way in game. If you start with -15% unrest penalty then everyone else, that means that you have -15% on growth, production and research from the very start of the game and that snowballs into other empires producing, researching and growing faster then you. They are far more likely to get to said 20 cities with LOWER unrest then you with no outside influence. Also, you rarely have opportunity from monsters and other factions to grow a lot cities at the start which means you have to make do with starting cities who produce 15% less then everyone else.

I really don't see how mechanics that force you to build balanced city be POINTLESS. I mean, the whole point of the system is that you need all the elements in it. This is actually great system, the only thing needed is that AI needs to adopt to it.

I really like the fact that forts have further purpose to help decrease global unrest from your empire. Gives them more purpose than just crunching out troops.

i disagree. if you actually invest so much time into building up some fortresses for unrest control, you really deserve it. it' not like you can just rush them to level 4- it takes 100 turns or more to get there. the level 5 trait might be overpowered, but it's almost entirely irrelevant to the actual game balance. you have to delay the game on purpose to get a city to level 5 before the game is over.