I have to say, with this season Moffat definitely leveled up. The only episode this season that I thought was bad was Sleep No More - sure, there were instances of silliness/dumbness here and there, but nothing I couldn't just accept as part of the show.
And the final trio of episodes, plus the Christmas special... they've been completely awesome. It might have been the lack of a distinctive "metaplot" for the season that made it great - in pretty much all the previous Moffat seasons, you've had season-long plots that are set up in episode 1, explored over the course of the season, and then resolved in the season finale. Season 5 had the Cracks in Time, Season 6 the Doctor's Murder and the Silence, Season 7 had the Many Lives of Clara Oswald (and suffered from being split over two years), and Season 8 had Missy in Heaven.
I mean, sure, there have been setups in earlier episodes. The Confession Dial was planted in episode 1, and you had Ashildr/Me in several episodes. But she was more of a recurring character than a plot device.
Now, the over-arching plot is nothing that Moffat started - Davies had Bad Wolf in season 1, Torchwood in season 2, Harold Saxon/the Master in season 3, and disappearing planets/the Darkness in season 4. But I think that particular bit is something that Moffat's not as good as Davies at, and I think this season has (hopefully) shown that he understands that and will avoid it in the future.
And of course, a lot of the credit for the season goes to Peter Capaldi, who has shown that he's more than a pair of eyebrows. I hope he'll be staying on for a long time.