Just a thought on a more organic method of marking out quests, giving directions and adding to the atmosphere and depth of the gameworld.
Between cities we have milestones, giving distances to local points of interest, cities, shrines, battlefields of yore etcetera. So that we know we are on the correct path and do not need quest markers or glowing exclamation marks, we can just follow the simple directions we have been given. And if a path or trail is not marked, is that not intriguing in and of itself.
Signposts could also mark the way at crossroads, perhaps with shrines for the pray