Over-populated Cities

[Oaty]

They are not overpopulated you just need to manage them better.

https://forums.totalwar.org/vb/showthread.php?t=39572

[Parmenio]

Plague, riots and crushing rebellions will reduce population.

[sapi]

A nasty trick is to give the city as a gift to someone who CAN'T make it in that turn, then re-capture the city and slaughter the inhabitents...it gets you top quality city with little unrest. I haven't used it much myself though

[Sin Qua Non]

Relcoate your capital closer to the center of your 8 30K+ cities. Use administratively adept family members to control the rowdiest of these cities. Public order buildings and taxes will solve the majority of your unrest problems. Once you get into the Large/Huge city range, though you must also use the oft forgotten family members and capital for the public order edge. A governor with high influence can keep the rowdiest of cities in order.
In the case of high culture penalties, consider upgrading all foreign buldings (including walls), and changing the temples, unless they are really giving high PO bonuses (such as pantheon to Dyonisus, etc.

[Somebody Else]

I say let them rebel, makes good siege practice, plus if you execute the lot, you can get buckets of cash. Or, you could enslave - redistribute the population to smaller towns, to make them grow a little faster (just remove the governers from the big cities first).

[Gith]

I go on a purge strategy. Keep a decent sized army around every group of 3-4 cities. Keep peasants as garrison. Any time the city gets too big to control, pull garrison out, hike taxes up to very high. Wait. Seige. Assault. Execute everyone and loot. You make money, you kill people, city is back up to 200%+ loyalty as soon as the garrison is back in. Repeat as necessary.

[Zorn]

Many peaople say: "manage your cities better, then you will have no problems with squalor and revolting".
That is true for roman factions, wich have many, many helpful buildings.
But other civilized factions have it a whole lot hareder.
Carthages cities can grow as big as romans, but cartage lacks many health buildings and hasn`t the option for races and games like romans have.
Sure, you can build you secret police, but that doesn`t by far help as much as having an aquaduct and monthly races would.
Disliking genocide, I can only helplessy watch as even cities without any culture penalty revolt.

[TheDuck]

A nasty trick is to give the city as a gift to someone who CAN'T make it in that turn, then re-capture the city and slaughter the inhabitents...it gets you top quality city with little unrest. I haven't used it much myself though

This is a continuation of the MTW strategy of using a province or two to help train armies up to higher levels of experience. I used it in MTW and I use it now. Its fun!

And how dare they wish to get out from under the 'fill in your favorite faction' boot? Revolt? Not for long!

Those were harsh times for sure.. the mercenary revolt during the 2nd Punic war saw 1000s of mercenaries crucified by the Carthaginians for having the temerity to lay siege to Carthage when the Carthaginian council refused to pay them. And the mercenaries were in the right!

[Spino]

Well whatever you do don't upgrade your farmland or the existing farmland of newly conquered provinces.

Tax the bejesus out of your subjects to keep birth rates low. Invest in buildings that only boost Public Order and not Happiness.

Mod the Governor's buildings so that each level grants +5% to Public Order (having an Imperial Palace grant a +25% bonus to Public Order really helps in massive cities). Kudos to the fellow who was the first to suggest that (can't recall his name).

Go one step further an grant greater Squalor modifiers to Health oriented buildings like Public Baths and Aqueducts (but this might affect birth rates so be careful).

Wait for the patch and pray that it addresses the current Population and Squalor issues...