Peasants-Troops-Specialists-Etc. (Meat Based Automation)
Currently there is some automation with machines but the main way of 'automation' of the time is missing, beasts and men(humans maybe half pig, half bear, half man??? maybe).
I would imagine a system where you would have to hire and if their is beds and maybe defined room and/or furniture you can get peasants. Their would be 3-4 classes. The aft-mentioned peasants which would do manual labor such as farming, wood cutting, mining, etc. The next one would be the troop class which be your defenders and attackers. The next one would be specialists/tradesmen whom will be your builders, crafters (autocrafters), and merchants. The last one would be nobles/advisers which can give various bonuses. Their also be beasts but they are their own system.
Peasants class would function buy having a sign, billboard, ledger, whatever object to hire them and you would need a bed along with any other objects needed for said bed such as a room or a cabinet or container etc. The peasant hired would need a path from the bed to his/her work spot to do their job and the peasant would need to be paid. The payment system is done by having a merchant sell goods to npc villages/towns/whatever though initially it can be foamed in by having the merchant just sell goods after x amount of time and then returning more on it later. Peasants would be simple works with a cheap wage only able to do basic harvesting tasks, they can barely defend themselves and thus need soldiers.
Troops/knights/soldiers/whatever, are the force you use to defend your claims. You can only have so many out based on what technology you have, server limits on deployments, and other factors. They would come in melee, range, and pure range. Melee would only fight in melee unless they can not reach the target at which point they will use a bow and arrow but have a 50% reload increase. Range has the similar logic but range, if something gets too close they will melee. Pure range will not go to melee ever. Guard spots would have to be deployed to have guards active. As guards die inactive guards can take their place, same logic with attackers. Attackers could have their own post practically but to summarize, they would attack player and npc villages and castles, they would require a siege engine manned by an engineer(specialist class) to start the invasion, as they die they would be replaced. When under siege they cause problems blocking roads out of your claim and if all roads out are blocked trade will stop money will run out and your guards will abandon the castle leaving it open for the invaders.
Specialists/tradesmen would be your engineers, merchants, crafters, and builders. They demand more money and more fancy stuff then the other 2 classes. Specialists would differ in payment though based on what they do. A crafter cost more then a builder, it would be builder<crafter<merchant,engi. The first merchant is free to help get players on the right foot with trade, maybe.
Nobles/advisers and animals...
Nobles would give various benefits varying on whom they are. You could have a general to increase amount of soldiers, you can have a patrician if their is a merchant cap, etc.
Animals would be tamed from the wild or bought from villages. They vary based on climate though some are pretty ubiquitous such as horses and deer. Deer do not exist in the desert, in fact the desert would the harshest place having few animals, or not it all varies. The main gimmick is animals like horses, donkeys, elephants, cows, etc. would serve as sources as labor or be used as machines themselves to help farming and other labor.