All in all, I enjoyed the season. Capaldi has a very (Tom) Baker vibe. I will say that I wasn't terribly keen on the Clara/Danny storyline (Caretaker was probably my least favorite episode this season, because frankly, it felt like a soap opera), though it was an improvement for Clara as a character. I also miss the "everybody lives" attitude, where the Doctor would try to save everyone no matter how impossible it is/seems to be.
One question about the finale - how does Missy travel between the "real world" and the Nethersphere? My apologies if this was explained and I missed it, but she's seen in both (in fact, she's in the Nethershpere for most of the season). And if the Nethersphere is where people go when they die... perhaps killing her wasn't the end.
Also, I really liked Osgood. Her death was the biggest disappointment of the season.