There is road building in Banished, but the townspeople will only use them if it’s an optimal path. They’re not the least bit shy about ignoring the roads if they can get to their destination via a shortcut. Since the roads do give a substantial movement bonus, the most effective roads are the ones which trace out the organic movement of the citizens.
I like both systems, but prefer the one in Banished. It’s rewarding to build a heavily used road system based on observing patterns.
You can put the roads where you want them by placing taboo zoning where you don't want them. Foundation's villagers have an unnaturally strong preference for staying on existing roads, so this is necessary if you want to straighten a road that was kinked due to an obstacle that no longer exists.
> In addition, the player never builds houses either. The townspeople pick where they want their house to go.
This is even less accurate; the townspeople can only build houses in areas that have been actively zoned for housing.
And their "desirability" requirements also mean that they won't build houses unless you've specifically built a lot of decorations nearby, so even if you zone everywhere houses will only appear in places where you make an effort to get them to appear.
And you are correct about houses. But it's still a difference from the usual medieval city builders in which house placement is something players do directly. Part of Foundation's goal of making their villages more organic and less grid. That was the point I was trying to make without getting into the weeds of how the housing mechanic worked in detail.
On a side note, I wish Foundation had the option for direct placement of houses. There were bugs in past versions which prevented house construction without enormous amounts of decorations. The current version is much better, but can still be mysterious as to why houses aren't being built in a desirable area with what seems to be plenty of room and the townspeople are wanting more houses. The reasons for the non-construction are not often clear. One thing I hope the game improves over time.
The "decision" to build a road from A to C was not really a top-down decision from the medieval periods. Rome built roads in a top-down manner that sometimes benefited the Empire as a whole... but Feudal Lords built roads in a smaller and more selfish scale.
The growth of roads at that time was more akin to animal paths (animals deciding to travel the same path as other animals: because the well-trodden areas are flatter and easier to walk). Its an organic growth, rather than a top-down planned growth.
I seem to recall playing a few games where roads grew naturally like this, but I've forgotten their names by now. Feudal lords built Roads more akin to Death Stranding (where the player builds a road to try to connect to the online community. Once the road exists, you gain the benefits of the entire community's efforts)
So people are talking about that kind of "locally selfish but community building" behavior. And also in a management simulator and... not whatever Death Stranding is (First person Post-apocalyptic UPS simulator?)
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Different mechanics for different eras of history. Again: Civ6 probably is akin to some Emperor declaring a road should be built between two major cities. But Medieval / Feudal society didn't have top-down edicts from an emperor (at best: maybe from the Pope but... the Pope didn't have that much power). Having a simulator for the medieval time-period could be an interesting gameplay mechanic.
Even ancient people threw gravel down (or logs) to help address this problem. But that’s a heck of a lot of work.
You do ant-like pheromone tracking for movement by all peasants of the world. (Each cell keeps a tracker, which gets incremented by passing peasants and decays over time).
Upon sufficient pheromone build up, your walking tile upgrades. Perhaps in the form of grass -> well-trodden -> dirt road -> gravel road -> stone road. Simple model of decay would be to simply downgrade back down the list. More complex might be that stone/gravel degrade into some special state to maintain permanence (dirt roads goes back to grass, but stone roads turn to grassy stone or whatever).
Your peasant/wagon/etc pathfind accordingly, getting speedboosts (or losses) by road type — and in your example, by road type + local weather (modeled separately)
You could also have different pheremone types producing different artifacts. Human pheremone only produces dirt roads at max, but wagon and tamed horse pheremone jump from grass->road with sufficient buildup. Wild animals only build up to well-trodden paths.