My suggestion:
- Outdoors only: You can go to the camp only if you are in an open area, away from enemies. Thus, it's not possible to skip to the camp from the Underdark, Goblin Fort, etc. In these cases, the party needs to go to a safe area for the long rest button to works.
- Sleeping bags: When they cannot go to the camp, the characters can sleep in sleeping bags. Just place the bag on the floor and click on it. It is also possible to sleep in the beds that you find in the buildings. Sleeping in a bag works just like a short rest. DOS has sleeping bags, so I believe it will be easy for Larian to implement. A message may also appear asking whether the group wants to light a fire or not.
So basically these two points are in direct conflict of one another. People (including yourself) say that you need to limit the travel to camp because it is not realistic, or it breaks immersion or whatever. But then you reference the crazy sleeping bags in DOS2 where you can just completely heal with unlimited uses? I mean what is the difference? That just seems like recommending some change, for the sake of recommending some change.