Sneaking is op because you can start a battle with a sneak attack from Astarion and then the combat tracker is just Astarion and the enemies that saw him, or maybe only the little pillar of light that shows up.
Once Astarion gets locked into the combat tracker you can still maneuver everyone else around the enemies sight lines and get a few more alpha strikes in outside of the combat tracker. My paladin -- in full plate -- can walk right up to an enemy that's frozen in the combat tracker as long as he doesn't walk into the sight cone.
I beat dror, m, and gut in the goblin camp all without any of them taking any turns because I was able to alpha strike them into the dirt by just starting combat with the whole party sneaking, and then walking them right up outside of the combat tracker.
Is there a party that can really exploit this? Ranger, wolf barb, shadowharts +10 party sneak, and an assassin rogue? Just alpha strike everything.
It's one of my biggest criticism. The premise push you toward minimizing the rest, and so does the gameplay (because it would be silly to just heal for free al the time, right?).
Turns out, I slept too little and I have so little development that required me to sleep to have them happen :(