We had crafting, now it's time for horticulture. What always struck me in Warband was that when we finally managed to take over castles, villages and towns, it turned out that their development was... well, limited. Bannerlord has changed very little and this aspect of the game is still lacking depth.
What if we could have our people set up orchards, gardens, plowing fields, or digging ponds for fish? We could then walk among the workers like a boss, catch fish, go into the mill and watch the flour being ground. Selling the stuff in faraway countries would be so much more fun.
Of course, agriculture could mean a whole host of extra problems to solve and tasks to do. We could bring new plant species to our fields from other lands, and face starvation after droughts and other disasters.