> Backstab, I really feel is bugged. I doubt it's working as designed. The player should have to move in stealth, outside of combat, to get backstab. A way to ensure this would be to have enemies face an active character within 2 meters of them. If you move the character around them the enemy should be rotating to keep eyes on the moving player.
I think you are contwining BG3 backstabs with the old 2nd Ed backstabs. I don't think BG3 backstabs are bugged at all and there is no reason a character should be stealthed to get them. They're just BG3's implementation of facing/flanking mechanics.