Creating trade routes/ relations with outsides cities could create some cool gameplay.
While trading does exist, its very basic, I propose trading routes. These routes are automated where you set what you want to sell and what you want in return. A hearthling ,probably on a mount, will go off the screen and into another community. This keeps repeating until you cancel it or you run out of material. This could also be a way to get exotic materials.
While the trade of goods already exists, trading services, such as building, fighting and mining doesn’t. You could hire hearthlings from different communities to do your bidding to either speed up construction or excavation, or to server your town. This could be done in reverse for a handsome payment, at the temporary expense of your hearthlings,
You also invade or be invaded by other towns. But creating better relations could result in cheaper goods and services.