Yeah, the explanation for Clara was pretty sensible; far less hand-wavey than I'd expected. This finale felt a lot more organic (and IMO moving) that "The Wedding of River Song" last year. Very good episode, and it wrapped up what I thought was a very good run this Spring.
I'd even go as far as to say that Season 7 in toto was the best season of NewWho. Some genuinely excellent episodes (Asylum, Angels Take Manhattan, Hide, JttCotT, and this one) and only two that I have no real desire to see again (Town Called Mercy, Rings of Akhaten). All very watchable, with none being terrible stinkers in my mind.
And Bedrockgames, you were incorrect, but definitely in the right neighborhood. Certainly closer than my thinking, which was that the Bad Wolf had something to do with it.