Game is great and Catherine is really cute character , what about adding food? Farms and markets became useless after some time, you could add food and need for it in countries and when you go conquer some country (troops have to eat too) you could add food rations (say people use x2 food then they produce x1,5 gold and if they have x0,5 rations they produce x0,75 gold and Catherine is angry in dialogues cause people are "disobeing her" not working at their best. Soldiers at war could die from starving if there is no food. Some countries could be made to produce more food or more soldiers.
REMEMBER it's only my suggestion, my idea and you probably won't use it, just wanted to share idea from my head...
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