Thoughts:
Capaldi is fantastic. He played it just the way I hoped he would, so I'm really excited to see how he develops the character.
The episode was ok, decent but not fantastic. I am bored of Vastra and her gang, although I do like the fact that they are occasional companions - I like it when there are characters that pop up from time to time without being in every episode (like Captain Jack used to do, for example). It makes the Doctor's world seem a little bigger than just companion + Tardis.
BUT I didn't like the ending. At all. I think it's pointing to a Moffat-style OH NO WHO IS SHE WHAT DOES IT ALL MEEEEEEEAN where there are no clues, just mystery that gets resolved 3 years later.
Which leads me to my final point - I want Moffatt to go. I am totally sick of his style, and I really wish that he'd left at the same time as Matt. As long as he stays then his foibles are going to stay - overly complex plots with no subtlety, and every female character being written the same way. Moffatt does "feisty" women, who have little else to their personality. I like women to be feisty, but not every woman is the same and it takes away from the immerse element of the show when the characters are too similar. Amy = River = Vastra = Clara = Jenny = all the others. They may have tiny differences, but the basic personality is the same each time and it's just too boring as a viewer.