Having played a good 25-30 hours of Pillars, I must say that it's a pretty damn good game. If I were to compare it to how much I enjoyed BG and BG2, I'd say it lies somewhere between the two titles with BG2 being on the upper end of the spectrum. Pillars is good, but it has something holding it back from being as great as BG2. I'm not sure what it was about BG2, but it had something special that makes it stand out against most other games I've played throughout my life.
If I had to guess as to what holds Pillars back, it's probably because it's sort of an experiment. It's Obsidian's attempt at making an IE-style game from scratch, including new world and mechanics. I think it's a good start, and I can't wait to see the next title in the series. By building upon the new world they have created, perhaps they can replicate that spark that made BG2 so special.
This. Oh, this so much. I really liked BG1, but 2 blowed it up and I loved it. I really like PoE, and if I had to say, I would put it above BG1 level of enjoyment, but to be fair, PoE had more modern graphics, it relies on stablished gameplay and and and ruleset, even if it uses it's own there's a reason it's considered a modern Infinity Engine game.
I can't wait for the sequel, it will be just like with BG1>2: it will keep everything good, and improve on what it can, to make a real jewel.