I actually don't mind all of the choke points around the map. It makes venturing into enemy territory feel more dangerous, since there's a chance your exit will get cut off and you'll get boxed in. The player is usually faster than most other parties that can pose a threat to you, and if there's a straight line out of every region it makes it feel like there's not much risk of overextending.
The thing about it is almost everywhere is some sort of a choke point. I understand the potential strategic value and encounter opportunity they can provide, but there is way too many of them. And many of these choke points is too blatantly extreme.
For example the stone way connecting two parts of Strugia, the same stone way connecting Western Empire and Aserai. These can only hold 1 party to pass in width, visually they are just a pile of few pieces of big rock. While there are also these long narrow passage that close in by length, acting as a whole session of choke points itself.
I disagree natural terrain, world map should be cater to other problems such as 'balance' or specific purpose, unless itself is causing the problem.
Well it probably helps with A.I pathing calculations and A.I war calculations as well. I don't disagree that it could use opening up a little but I don't think it ever harmed my gameplay.
Interestingly I actually find ai having trouble with pathing, and the terrain often severely influence the world. For example, I witnessed many times an army or single/few stronger party block a passage, but the opponent's ai decide they must pass, end up with a situation you have one side can essentially push-straight and the other side is repeating flee-engage-flee-engage, and so the war is decided. And these situation of narrow passage not only influence war, but the city even the whole economy, the caravans and the villagers got blocked too. Sometimes if just a bandit hideout happens to spawn in the narrow passage, the bandit grow in strength and the city start to starve, because the suppliers got blocked.
These situation is very blatant at the places with narrow passage. Especially Northern Empire with it's west part mostly consist of passages-valleys.