I will say the ending was the best part of the game for me. They did a good job with that. But what I love is that they actually have a post game setting after you finish the story. They don't just drop you at the beginning of the final mission after the credits. No, the game world actually acknowledges your victory. If feels good to see that all my efforts wasn't just washed away into game oblivion until the sequel is released.
My advice is that folks keep their sidsquesting to a minimum and wait till after the end to do the extra shit. Focus on the main story, the loyalty quest, and the lost arks. There maybe a few other crucial missions relevant to the main campaign besides that, but don't bog yourself down.