The Judoon episode borrowed a lot from RTD era Who. Judoon, Chameleon Arch, return of Jack Harkness, and all. In some ways, that was good; in others, it was a little depressing, because it was a reminder of how far Who has fallen, starting with the Series 8 rewrite of Clara Oswald into a pathological liar and generally annoying cunt, and accelerating when Whittaker started Christopher Eccleston impression-ing her way through the role. I keep expecting her to blurt out, "Every planeh's goh' a nohf!"
Oh, and of course the alternate Doctor has to be played by a Novelty Diversity Hire, too.