One day I’ll have to watch the rest of his run with Bill. I loved him and Clara together and I loved the first episode he had with Bill, but after that the episodes couldn’t sustain my interest as much.
Danny Pink was too good for Clara. He deserved someone who genuinely loved and respected him, and I’m incredibly disappointed with how his storyline played out from start to finish. The Doctor treated him like dirt. He would’ve been better as a companion for [redacted], alongside [redacted].
I feel very similarly regarding Deep Breath.
The whole dynamic between him, Clara, and later on Danny in season 8 felt just so jarring.
That said, very early on he became one of my favorite Doctors nonetheless.
Capaldi is just so good in the role, and for me, there were brilliant story moments (and with episode 3, a favorite story) to be found in season 8.
I am one of the few (?) who really like Last Christmas and with season 9 the stories became ‘better’ (in my subjective opinion). More interesting. But probably still with too many elements designed to make the main character unlikable…
Still, two of my most favorite scenes of all of Doctor Who are in this season: Twelve playing guitar on a tank and Twelve, in response to Clara’s death, becoming absolutely terrifying in a few short lines with Ashildr.
I think he is old. Borrowing a line from the character of Andromache in Old Guard: too old. Or at least he feels this way.
He is in a regeneration that should not be (this was all before the retcon of the Doctor’s origin). What we saw was how he put himself back together over time. How elements of his old selves came to the forefront - there were some scheming elements of Seven, I think, Ashildrs ‘genesis’ showed quite a bit of Ten, etc. - and vanished again.
How he coped with his own guilt, again. This time by projecting on Danny and for at least a long time not being able to see what was going on. Even as he a) should already have coped with that and b) he should have had enough meta-awareness to catch himself. But well, that was not what he was able to do in the first years of his ‘out of bounds’ regeneration.
Well, at least that’s how I interpret what I saw. And as much as I like Twelve, I do not think it was very wise for the show to make it hard (imho) for the audience to like its main character over such a long period of time.
So, for me, season 10 was like a gush of fresh air. Finally, the character I liked so much was in stories that were not only interesting but also enjoyable (mostly 
).
All that said, Twelve is absolutely in the Top 3 of my most favorite Doctors. Many, many, many of the stories he is in are not.
But those are just my thoughts.
12 and Clara’s relationship makes me nuts. I love them. Emotional affair is a good term for it. I think they both know it’s not a healthy relationship, but they keep staying together and egging each other on. And we know how that played out. Love them or hate them, they’re a really unique doctor/companion pair in the revival.
I see this mentioned a lot, but:
My only regret is that they didn’t save the ‘brand new set of regenerations’ for Jodie, and have her the first of a set of new faces which are different from the status quo (women, PoC, etc.) then we’d have an in-universe explanation for that - and also why the pre-Hartnell Doctors were all diverse - for some reason, the TV Doctors were stuck in “white male mode”.