Here's what bothers me: this fight was already difficult but beatable, and not necessarily by cheesing, but it's definitely not going to be your first playthrough, because if you play like the story would lead you to, you all walk in together like lambs to (literal) slaughter. Only way I have won (not trying crazy shit like sending in two invisible imps, etc.) is to put my spellcasters up top, and make liberal use of potions of speed and strength. But now, when I see BS like an alleged 5th level NPC with 91 HP, I have to throw the BS flag. There is no way any 5th level character can amass 91 hp; therefore, any NPC with 91 hp is not 5th level. If Larian is going to insist on putting adversaries that are that strong (and hostile) on the battlefield, they need to assign them the appropriate level, and reward EPs accordingly. If I roll up a Gith fighter, best I can hope for at 5th level is either +2 Con bonus and the Tough feat (+4 HP per level for a total of +20 hp for a 5th level character) or +3 Con if I take a Con score bump for my ASI. They could give a 5th level fighter max HP for every level (which ain't kosher), AND the tough feat, and still be 21 HP short. BS.
I will say, since the latest update which puts all the gith in gith half-plate, I am now inspired to create a run-through where all four characters can wear half-plate by the time they hit the Underdark. (Tav, Lae'zel, Shadowheart, and either Wyll or Astarion with Moderately Armored Feat from 4th level ASI. Not going to Stealth anywhere, but don't need to!
NPC enemies work differently than PCs in D&D. For simplicity, most enemies don't have the full amount of abilities (e.g., fighter's battlemaster maneuvers, second wind, or action surge) that PCs have, so in exchange get additional health and simple abilities like extra attack at lower "levels". Additionally, enemies in D&D have Challenge Ratings, which is supposed to correspond roughly to the level of the party, not to a single PC.
The issue here is Larian's insistence in giving enemies "levels," which doesn't really make sense for most enemies but naturally leads to comparisons to player level.
E.g., an Ogre is a CR 2 monster with 59 HP and a single action (attack once). Clearly an Ogre has more HP than a level 2 fighter, but wouldn't make any sense to label them as a level 7 enemy (which is the # of Hit Die an ogre has). They are CR 2 because alone, an ogre is supposed to be a relatively easy for a party of 4 level-2 adventurers to defeat.
Similarly, a Bandit Captain is also a CR 2 enemy with 65 HP and can make two main-hand attacks. A "level 2" fighter can't make two main-hand attacks every turn and has nowhere near 65 HP, but a CR 2 Bandit Captain has these abilities because it's balanced for fighting an entire party of level 2 adventurers, not one-on-one combat with a single level 2 character.
tl;dr: Either players need to not compare the "level" of enemies to character levels, Larian should replace enemy "level" with enemy "CR", or Larian should remove the numerical labeling of enemy strength entirely.
