It might seem like a silly question but I'll ask it...
NPC weapons/actions/etc also create noise?
If yes - can the player detect NPC's (approx?) locations from the noise they create? i.e. can the player hear?
I know we have stealth mode to sneak around and visually scout with.
It would be rather strange if the player actions create noise whilst the NPC's are completely silent/in a vacuum.
Noise will be an excellent mechanic - it'll add a certain amount of randomness and variety.
It's far too easy in Fallout to pick off enemies one-by-one (i.e. Khan raider camp) unless they're grouped together.