The third factor, and a factor which was a late addition, is technology. You cannot stop researching techs, barring absurdity such as selling your science buildings (which will lower your happiness from illiteracy anyways). This is what tends to screw your happiness in the late game. You invent ballistics and your people are suddenly impoverished. I invent biology and suddenly they are bored. The problem here is I don't get more culture with every tech, only like 1 in every 10 techs has a boredom reduction, or a poverty reduction, or an illiteracy reduction. So if I have boredom, my only way to reduce that is to research towards the stadium, which means I have to discover 7 new techs all of which cause even more boredom.
Tech increasing unhappiness works just fine for the early parts of the game, however I'm seeing 0 complaints about happiness from ancient to medieval. Part of the reason it works out alright here is because there are so many buildings and other things being unlocked that almost all techs have something that fights at least one kind of unhappiness. I think around industrial era (where all happiness complaints occur) its a bad feature though. I can stop growing temporarily to deal with happiness issues, I cannot stop discovering techs.
Also I don't like distress. If you are missing hammers, you are already short on the buildings that fight unhappiness. Food causes you to grow so its weird, the food aspect just makes specialists heavy strategies better IMO. The only city that has lots of food but isn't growing to match that is working many specialists.
PS- if you are constantly having happiness problems, take inspiration every game. When happiness is a factor its uncontested for the strongest follower belief.
I'll just point out that i indicated that all of those will be a problem once new mechanics was introduced, without even trying the game. It was obvious, but nobody listened.
I don't like unhappiness increase with new techs - i understand the idea, but it just does not work the way it should. I understand the problem with integer values, but i'll throw an idea here. Can it be caused by % modifiers? I mean if you are in Classical - you research a tech and your needs increase 10% - from 5 to 5.5. And when you are in Modern - you have more citizens AND more yields per citizen. And same 10% is now an increase from 50 to 55, which is big and very hard to get. I may be wrong though, i'm not sure.
I don't like distress either, it is artificial and awkward. I still think crime was better. (From a gameplay perspective, i understand that G didn't like the code)
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