I think that there should be a way that new settlements either organically appear on the map, or the player, through a lot of funding and series of quests, can help make a new one, where they can collect taxes from. Perhaps at a player-settlement, you could hire extra mercenaries to train there, or defend the settlement, and you can come back and swap members of your current party for the garrison and vice versa.
Additionally, I feel like the road network as it is leads to very long travel times. I think a method of building new roads should be implemented, so the player can pay to pave a road through a mountain, rather than having to spend 6 days to go around the mountain to get to a town not actually that far from the other side of the mountain.
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