I was never a fan of Time of the Doctor being made a Christmas episode. Then they did the same thing again with Twice Upon a Time, but at least then it was a little more of a one-off with the Twelfth Doctor hanging out with an exaggerated caricature of the First Doctor instead of spending 90 minutes wrapping up all his loose storylines.
That being said, I actually like Time as a finale to Smith’s era, it was just dumb to make it a Christmas special instead of its own thing.