I just created my account on this forum to say the exactly the same thing!
I hate the repetition of quests over all game genre. Find something, fight pirates, transport something, trade. Maybe sometimes i just want to plough the farmland i own, watch a traveling medieval theatre type play about the latest gossips of events in general, borrow money to others for investments.
It would be nice to be able to edit castle walls or custom fortify villages. Improve farm output by (almost) manually digging irrigation systems or fountains with donkeys rising the water from them. As the lord of a village you could let people manage themselves or tell them to plant seeds for wheat or raise vineyards if you are near a hill or cut down an area of trees and plant fruit trees and if people start starving because of your leadership the people may revolt or starve and leave or you will have to pay for food for them from selling what they produced. If you are near mountains you could try to start a mine of stone or fail because the land isn't stable or find silver and get rich.
I know many would not like to enter that much in detail and probably 99% of people play the game for the fights and gore and hack-and-slash action but think about the power of games like minecraft where you can plough the land and watch the sunset from something you jut finished building. People like rising a village with (almost) their own hands and see it as it grows after fails and hardships, after raids and fires.
I would like the game to be able to evolve from one stage to another organically.
Start as a lone wanderer reach a farm, plant fruit trees, wheat and , make a profit and invest in a traveling pharmacy. Get out of the business before people find out it's a scam; make a profit and buy a herd of cows. Buy some land and start a tiny village by hiring villagers to take care of the cows. Pay a few men to protect the farmland, build a hall, build fountains, raise a wood wall, build houses outside the wall for more villagers, cut down a large area of forest for grazing, make charcoal for a lot of iron. Make and sell some weapons, pay bandits for local protection, get involved in local politics, create an army.