In Pride of Nations, commerce is extremely important, as it was historically. And commerce often means having a large merchant fleet at your disposal. We had to design a system that represented with good approximation the intricacies of commerce in the Victorian era, while trying to keep it manageable by the player. We knew what we wanted though, so we started by designing commerce zones.
The game would revolve around the central concept that merchandise units are produced within a trade zone, and you have to pick them up from this zone or it would be wasted. Also, we wanted to have buying and selling done by transactions between two countries. This is one of the great things about a turn based engine, using 2 seconds to calculate how transactions succeed between countries is well affordable, while doing that in a real time game is too time consuming.
And so the commerce is handled by transactions. A country proposes goods in a given trade zone (most of the time in the trade zone where his capital resides, this is quite enough in complexity), and customers, if they can reach this commerce zone (and you generally need a commerce fleet for that, as long distance land trade was not economically profitable, except for luxuries) will buy your products. But before buying it, they will perhaps compete with other countries. For example Great Britain is a major exporter of coal, and France needs coal. France and other countries will propose purchases in the Great Britain trade zone. So there will be competition, and who will get the deal depends on many parameters, like your commerce techs, your relationships and how much money you are willing to spend.
Transactions are done in a way that once set, and unless something major happens, you don’t have to tweak them every turn. The same applies to commerce fleets. You’ll not have to hunt constantly across the continents to spot new opportunities, as commerce fleets operate from only 22 sea trade boxes. Twenty-two seems a lot already, but when you have 3 commerce fleets, you’ll generally put one nearby Great Britain (and she will be able to trade also with France and the Low countries), one nearby USA and for the third, well, the choice is yours. So really, there is a minimum of micro-management here, given that the trade is quite concentrated in only a few areas.
A nice side effect of this decision (to use only a few maritime boxes) is that they are ‘promoted’ to ‘convoy boxes’ in time of war. In this way, Pride of Nations is able to simulate the submarine operations of the Great War. Place your subs in a maritime box and try sinking some trade ships, to disrupt the enemy’s economy, while evading escorts! Or perhaps you want to go for a more direct approach by blockading the enemy harbors, thus preventing them from operating as an unloading point for merchandise? This is feasible too!
Screenshot 1: view of a maritime trade box, where you handle your commercial fleets and the small but very important Trade window belonging to the Great Britain trade area.
Screenshot 2: Portuguese AI is maintaining a commerce fleet in the gulf of Guinea while a US patrol cruises nearby.