The lack of fast travel got me the most memorable moment in the game: i fought my way through the catacombs inching forwards very slowly on my first play through. But i did make progress through the scary skeleton dog area and the world finally became bright again only for there to be a yellow fog wall i could not interact with. The lack of fast travel made it so i had to fight my way backwards through all that scary stuff again and while that was like 15 years ago i still remember it.

But also yeah I think it forced some good world building to have no fast travel. But part of the charm of the world is also seeing ash lake and lost izalyth through vistas in completely different areas as the whole world was based off being on a big ass tree. I have bought an artwork of that even and put it in a custom made picture frame for 80€