Ok, you are mainly doing two things "wrong", if you want to use that word. First off, building the farming improvements is generally a bad idea. While they will help your city grow faster, they also will make it grow larger. Large cities are rebellious cities, so it's best to avoid that as much as possible. I no longer build any of the farming improvements, they just aren't worth the hassle.

The other issue is enslavement. That's a double whammy. First you move population into cities that might not need it anymore. And second, you miss out on the extra denarii that extermination brings in. Early in the game, enslavement isn't a bad choice. But in mid-late stages, extermination is the way to go.

The other issue you need to keep track of is your military costs. You'll likely end up with a lot of 'backwater' cities that are in no real danger of getting attacked. Stationing a lot of expensive troops there is a waste. Move them to the front, and garrison the city with peasants. They are the biggest stack size you can get, and they have the cheapest upkeep for their size.

Bh