I just finished this game right now.
First off, this game ranks probably in my top 10 favorite games of all time. No, really..I think I started getting into games around 1995, so this game IS good (to me at least).
The ending could be bad or good. To me it really was neither. I enjoyed playing the game entirely, and never found a dull moment. This game really got better from start to finish for me, where as a lot of games start off good then just fall off the edge. If this is the last Divinity game to ever come out, then I'd lean towards the ending being a thumbs down. If Divinity 3 comes out, then we really won't know whether this ending was good or not till then.
The ending also had a very "Sacred 2'ish" feel to it. If you've beat Sacred 2, you'll know what I mean. However, the game was just too fun the entire time for me to be mad at a rather lackluster ending. Sure, I would have liked to have fought Damian at least, and seen previous characters such as Lovis play some role towards the end, but hey - it is what it is. And, the Hall of Echoes was rather cool, though the "bosses" seemed too easy the second time around.
Either way, despite an ending which I really favored neither good or bad - the game is terrific.
