The problem isn't the current resting system, the problem is that you can rest while the game is time frozen.
They need to implement triggers that changes the world if you start something and they sometimes do, like with the Gith patrol and Laz leave your party and run to the patrol, if you do just about anything else than following her, she gets killed, because time still passed.
Killing the goblin priest might allow for hiding her body and rest, but attacking the front gate and most others in the current design should result in everyone gathering in one single room, making a close to impossible fight.
Also why can't we assassinate the goblin leaders, they all seems like fight that should be impossible to hide. Especially the drow one where 3 gobs ignore the fight even while I stand on top of the wall shooting into the drow and friends in line of sight of them, not to mention in line of sound.
The entire goblin area could use a major overhaul to allow for fighting smaller groups and it being easy to see why it doesn't attract attention of the rest, AS LONG AS YOU DON'T LONG REST in between encounters and that you destroy the drums.