The game design could also make fast travel more immersive. And yes, that will probably mean having less access to it.
1) players open a beautifull map that represent the area. 2) players click the icons on the map to select an area to fast travel (BG1) 3) players are teleported to the right entrance in the area (in exemple you can reach the blighted village by 4 roads. If you were in the north of the map you're teleported in the north of the village, at the closed gates). You have a 4) a few hours have passed
Done.
This is the same fast travel system except that your characters have walked rather than being magicaly teleported.
But it require one of the most important and one of the first thing to make such a game a bit immersive... a day and night cycle and a world in which days and hours exists.
If you don't want to break any sense of immersion without a real full cost day and night cycle make it like it was done 20 years ago.
1) 1 atmosphere during the day with NPC doing their NPC's stuff. 2) night has come. Beautifull cinematic to make the transition. 3) 1 atmosphere at night with NPC's doing their.NPC's things at night. You don't need a bed for everyone. Some activities in the night doesn't require a bed. 4) day has come. Beautifull cinematic to make the transition.
Making such a game without a day and night cycle is a shame.
