I was thinking a cool mod would be one where npcs will become hostile if you just walk into their house/room uninvited. A "knock" prompt could come up when you interact with a door of a place that would then act as an interaction with an npc (they would come outside and chat to you). NPCs related to quests would only give you free reign of their home if it was a requirement of the quest and even so, these rights would be revoked as soon as quest completes. Probably have to be disabled for essential quest npcs and the likes. You could even have a prompt that says (open door carefully) and the chance of the npc not hearing it could be affected by time of day and players sneak skill as well (as well as a bit of good ol' fashioned luck, maybe). You could even have a prompt that says slam the door - it wouldnt have to do anything except play a door slamming sound and could be used for rp purposes (ie if youre character is pissed off at the npc in question)
This would also have the side effect of making sneak/thieve builds work even better, and i think in general would add a really nice flavour to the whole game
I don't know a whole lot technically about the game but I was thinking maybe it could use the existing steal function? i know some npcs like ncr rangers go hostile as soon as they catch you stealing s*** but im not sure if you can combine loading another cell with this.
Maybe this is a terrible idea and would end up royally f***ing the balance of the game, but who knows
thank you so much for reading!