Hello! I am entering this conversation a few months late. I came across this thread when I searched Google for a possible canon explanation for there not being roads in Calradia. Some of what people have said here are interesting concepts! Old roads existing from the Imperial days deteriorating (or being fixed up by new lords!), new ones being constructed, and the maintenance such projects would require are nice ideas. I also like the suggestion that trade caravans would prefer using the roads to save time, but that would mean it is more dangerous as bandits would be there ready to take their cargo. Maybe they would run away from the bandits into the wilderness, and if they got away or beat them if engaged, eventually go back to a road to travel on to their destination if needed?
I want to bring up another suggestion, from an observation I made while on campaign. In the main sea in the south of Calradia, there are islands. There are islands elsewhere too, off the coast of Vlandia, or near Sturgia, for instance. In real world history, the sea was used for travel extensively! There were cities on the bigger islands, and civilizations that lived and died on them. An example are the Minoans of Crete, or the Sardinians and Corsicans. Britain is the greatest European example. What I would love to see is the ports on those port cities actually be put to use... sea trading, settlements on the islands (!! is that too much to suggest?), and the ability to disembark your army to an island. Perhaps the intention at first in the earlier games and now was to downplay the importance of the sea, to make the islands be deserted since the people of Calradia have no interest in colonizing them or utilizing them for trade routes, as was done in reality?
In my current playthrough, I have a port city in the Southern Empire under my control. It's my only fief and it has been my only reward from about 50 hours of gameplay. All I'm saying is it'd be nice to put my port to use and maybe in the least get some sort of extra, sea trading port bonus to my income. And don't get me started on income. I have way more gold than I need, really... I wish I had more to spend it on.