My primary problems with the game are...
Nonsensical writing. Characters are written pretty well, but there's a bunch of absolutely dumb shit happening above that level (read: plot, story, motivations, yadda yadda). This really isn't that unusual in games so it doesn't bother me that much.
Easy as fuck. I'm on Path of the Damned and am still having trouble finding a challenge. 95% of the spells don't really have any punch to them. I find myself leaning on buffs/debuffs because they always land, whereas damaging spells are far and few between. And then the rest of the 5% are blatantly broken shit like Paralyze, Petrify, or Charm. I Charmed a motherfucking ghost boss. What the hell is up with that? And I frequently "frighten" creatures that are undead? There's a lot of stupid crap going on with the combat all the time. The further I get into the game, the less I like any of the scenarios, too. Like others have mentioned, there's a repetitious nature to it, and there are no real set pieces. I mean, you don't have to go the Blackguards puzzle-route, but goddam, there is little going on combat design-wise. I think with RPGs it's really fucking easy to mask poor scenario design, but honestly PoE is the equivalent of a Mario game where there are no gaps in the floor or blocks to jump on and all you face is a long line of goombas. Totally agree with most people here. Where's the effort?
The world isn't really that responsive. I've never been the biggest BG2 fan, but it does do one thing well which is draw you into that high fantasy world. I liked that if I started some shit in town people would come by to tell me to cut it out. I'm beginning to wonder if the no city-magic laws of Amn were actually intended to keep narrative structure, maintaining one's suspension of disbelief. I say that because in PoE I'm throwing fucking fireballs, indoors, in a bar-fight, and nobody says a fucking word about it when it's all said and done and it's really noticeable and kinda pulls you out of the experience. This goes along with the general lack of reactivity mentioned by others.
No real motivation or villain or consequence or much of anything. I really enjoy the lore and setting of PoE, but what the fuck am I doing in it? I've been in Defiance Bay for hours doing this or that bullshit task and nothing is really unfolding. Again, not a big BG2 fan, but it did have you chasing a villain, and it did have villains kinda fucking with you. You had dragons fooling you into killing knights, djinn doing magic tricks, you had some uber-enemies sprinkled around the world sitting in doomsday coffins, and great monsters being worshipped by cultists. Like there's so much shit going on in BG2 even off the main plot of chasing the Big Bad Wizard. PoE is mostly, uh, well there's little feeling of consequence or threats. I'm not gonna run off spoilers left and right, but at least in Defiance Bay I've already come across a few things that I felt for sure would have consequences but they never did. I'm sure the exact same thinking behind the weak-ass spell system is the exact same thinking behind the lack of strong villains in this game. Everybody's pulling punches. There are no BG2-esque, There are people in this world far more powerful than you, stuff going on. Nah, I'm just beating up shapeshifting drug dealers (wut) and child murderers. When a bandit eyed my party up and down, glancing over what was for sure a night-time nuclear light show of magical effects, all he had to say was, Nobody touches my blade and survives!!
After dispatching him and his presumably reluctant gang in a matter of seconds, all I could think was... where the fuck is my equal? Like who here is bossing me around? I think that's what's missing.