Hi!
Since, if I recall correctly, the dev journals have stated that people found the resource system with stored/transported quantities to be un-fun, I've decided to attempt a design with which to replace it, and would like some input.
I decided to start off from the basic design principle that strategic fun is making decisions under scarcity. I also know that the new system needs to be easy to manage, having preferrably no minutiae and minimal UI requirements.
For a decision to be meaningful, making it should have a cost. Different options should be different. There must be a right choice, but which one is right must depend on circumstances. These circumstances might be determined by the map, but should also include the effects of previous choices.
As an example, I use the choice of which metal to use for your troops' equipment.
Options:
1. Copper is common and easy to smelt, but weak.
2. Iron is common and better than copper, but is harder to smelt.
3. Bronze is better than iron, but requires both copper and tin, with tin being uncommon. Because of the two metal requirement, extra manpower is required.
4. Steel is better than bronze, but requires iron, coal and marble. The ingredients aren't too rare, but the manpower and energy requirements are steep.
5. Mithril is better than steel, but is really rare.
To implement the creation of these equipment types, requires manpower, resources and time. The cost to your economic development is significant, so you have choose carefully.
Resources aren't stored, any surplus is assumed to be sold to the civilian economy for profit. Also, the resources travel along roads to calculate availability. Building an iron mine, should, for instance, provide one unit of iron. Building an iron foundry (or whatever) then uses up one unit of iron and produces ten units of iron equipment. A barracks that is training a unit with iron swords, and bronze armour would then use e.g. 3 units of iron equipment and 7 units of bronze equipment. If other buildings are already using a resource up, that makes it impossible to create a building/unit that uses that resource.
All metal smelting requires coal, which can either be mined directly, or can be made from wood. Copper needs less/no coal and steel requires coal for each step of its production. This emulates the difficulty of smelting the different ores.
To simulate manpower, each building reserves a proportion of the city's population to work in that building. If the population is decreased to below the reserved level, buildings are destroyed appropriately/randomly or something. Unemployed people should pay a negative amount of taxes to simulate crime, so that you cannot just save them up until you know what the best choice is, or to act as a buffer to population loss. This system can replace the current city-levelx2 = usable tiles system.
It takes time to build all this infrastructure, so you cannot at a whim just switch from bronze to iron, for instance. It will take several turns to get the new economy up and running, meanwhile you cannot produce bronze or iron. Something to do in times of peace, not times of war.
As an example to prove the significance of these choices, take the following scenario: You find a source of tin, and have already found copper. You know iron is common and tin is uncommon, so, if you decide to use bronze, you might not find more tin, and as you expand your limited amount of bronze could become a liability. If you decide to go with iron in stead, you will probably have to break down your copper economy though.
Now, I guess this sounds complicated, but to show how simple it is, I explain the most complicated material;s process from a user's perspective:
1. I have unemployed people.
2. I have two iron, one coal and one marble available.
3. I build a coal mine, two lumber mills and a marble quarry.
4. I build two wood furnaces to turn wood into coal.
5. I build two iron mines, which uses two coal to produce two iron.
6. I build a steelworks, which uses two iron, one coal and one marble to produce 20 steel equipment.
7. Now can tell two barrackses to train my Fist of Steel elite troopers at the same time, or I can tell four barrackses to train pikeneers at the same time.
If you lose a mine, the closest active smithy to it should deactivate. If you recapture a mine, the closest non-active smithy to that mine should reactivate automatically. This causes that to reclaim the manpower, so that you can do something else with it, you will have to dismantle the building yourself. An inactive building should have black in place of your national colour, so that you can easily see the status. (That would unfortunately mean that black cannot be a national colour.) There should also be a notification in the turn report, of course.
With regards to the UI: the only extra displays are a resource availability panel for the city, and the inactive building colour-change. There are no extra input interfaces required.
I believe I have shown clearly that my design is simple to use, gives interresting choices, and requires minimal UI to manage.
If you see any flaws (from a gameplay perspective) I'd like to know of it. Maybe we can modify it subtly to fix it.