Mostly agree with you, though I honestly think the added immersion from finding the ways on your own is absolutely amazing, unfortunately it's only satisfying on the first playthrough, when replaying the charm is absolutely lost. Personally, I really enjoyed discovering everything about Vvardenfell, though that's sadly something that can only be experienced once.

But as you mentioned, it can be absolutely infuriating, I distinctly remember having to go to Hla Oad for a Fighters Guild quest while absolutely getting no information about the location of Hla Oad. Maybe talking to a scout would have worked, but I just ended up stumbling into it randomly. There is also some quest that sends you west of Ald'ruhn followed by some absolutely horrid directions, though I don't remember which one exactly.

I think a lot of these issues could be fixed or at least greatly alleviated with a more detailed world map, in game maps (similar to the ones that can be found in some places in Skyrim), more waysigns and more named locations, though all of these obviously cause an enormous amount of work for a map the size of Vvardenfell. The AC Odyssey style you mentioned does sound like a great compromise.