Forget everything you know about the WoM economic model. Food is gone (as it exists in WoM), housing is gone, global population is gone, specialists are gone (improvements don’t use population), materials are gone, resource multipliers on city level up are gone, fixed build times are gone, unlimited improvements are gone (you can never make more than 1 of an improvement in a city).
In Fallen Enchantress a city has one production queue. The amount of production a city generates is based on its population, with some modifiers. Small cities take a long time to produce big things. Since there aren’t specialists (ie: consumed population) or materials if you have the tech to produce a unit or improvement you can generally stick it in the queue*. It’s not hard to fill up a city with 60 turns of things to produce (or to cancel items out when something changes).
Population is local and a city’s population is broken into Farmers, Workers and Rebels (we may change the name for this last one, Dissidents? Angry Hobos?). Farmers produce food, a little production and pay taxes. Workers don’t produce food but they produce more production and pay taxes. Rebels don’t produce anything and don’t pay taxes. You cities automatically allocate enough farmers to feed your population and armies (meaning the more armies you have, the more farmers you need, the less workers you have and the slower your production is). Your goal is to have as many Workers as possible. Minimizing Farmers (by investing in food producing buildings and capturing food resources) and minimizing Rebels means more of your population is Workers.
The player can set his Tax Rate. The tax rate determines how much your population pays you each turn, but it also increases Unrest. Unrest creates Rebels. Although it never hits the point where more Unrest means less gold (higher taxes always give more money), higher taxes always mean less production. Life in Fallen Enchantress is expensive, monsters don’t all give gold (in fact few carry gold).
Growth replaces Prestige and is the rate at which population is added to your city. It is influenced by improvements, local resources, champions in the city, and the amount of cities in your kingdom (the more cities the slower your growth to balance small empires vs large empires). Since population determines your production and taxes, your high population cities are the backbone of your empire.**
Whenever you build a unit the population comes out of the city that produced it. In effect armies are population that isn’t contributing to production. Making a stack of 9 spearmen is a serious investment. Disbanding units returns the population to the nearest city (if you are in your borders). When you build Pioneers you can build them at all the same unit sizes as your other units, and the amount of Pioneers in your stack takes that amount of population away from the building city, and starts the new city with that population.
Improvements have fun with these mechanics. Slums increase the cities Growth and Unrest. Governmental type buildings reduce Unrest, the Mint of Ruvenna provides +1 Gildar per Worker in the city, etc.
Most importantly, from a city specialization standpoint, when you level-up a city you get a random list of improvements that you can unlock for that city. They are based on the city level so the improvements you get at city level 2 are a different list than those you get at city level 5. There are rare improvements that may popup in these lists, especially at higher levels. For example, when leveling a city to level 3 you may have the option to unlock any of the following improvements for that city:
Apothecary- consumes a little mana, provides research, champions can buy Healing and Growth potions.
Bazaar- +2 Caravans, the city produces +50% more Gildar when nothing is in the build queue.
Bell Tower- Improved Production and free Peasant defenders if the city is attacked.
Brewery- Reduces Unrest and reduces Production.
Infirmary- Small Growth bonus and all injured units in your city are completely healed.
The player can pick one, and it is only unlocked for that city. The player still has to build that improvement. We may decide to place it for free, but I like that the player has to build them because it allows me to balance them on build costs, but in general they have low build costs. This is how we specialize cities, and this is our reward for players that choose to run small empires so they can race to getting up to city level 5 unlockable improvements like the Onyx Throne (-50% Unrest, -10% Unrest in all cities), Pyre of Anniellum (provides mana and increases the power of Fire spells), etc.
Terrain matters. Terrain has tile yields, and a city gets the tile yields of the tile it is founded in and all surrounding tiles. In the beginning this is a significant amount, as the city grows this is less and less of the total food and production amounts. A city on fertile land by a river will get some bonus Food and Gildar each turn as well as having access to improvements that can only be built on a River. A city in a desert won’t get any of these base yields, but may be worth it to grab important resources. Tile yields don’t extend as the city extends, they are only those 9 tiles. Tile yields aren’t intended to be the root of the game. They are a boost to new cities, turning a city that may take a while to produce anything real, into a reasonable city relatively quickly (your capital gets free starting population so it skips the new city slowness). City on good tiles are better, but it isn’t game winning, especially later in the game.
* Metal and crystals are still resource requirements for some things, most notably advanced armies. So we still have the concept of “you can’t build that until you build up x resources” but its used for special things, not everything.
** When a city is taken in combat half of its population is lost. Also when units die their population is forever lost, giving us some outputs for the population system, it doesn’t continually build. And, although warring successful wars has its benefits, it can be costly too.