Moffat told Digital Spy that there are two monsters he wished he'd featured more – one of his own creation, and one a classic menace from the 1970s.
"I wish I'd done more with the Autons," he said. "I really like them."
Robots resembling shop-window mannequins, the Autons did appear in series 5's finale 'The Pandorica Opens / The Big Bang', but haven't featured on the show as a major villain since 2005's 'Rose'.
"I think I should've done some more with The Silence," Moffat added. "That was a good idea that I didn't revisit, and I don't really know why I didn't."But I did 42 episodes, I co-wrote more again, probably the same again re-wrote, so I think really I've covered everything. I think it was time to get rid of me!"
Looking back over his time on the series, Moffat cited "all the shows we made around the 50th [anniversary]" as his proudest achievement.
"There was some phenomenal television there – I can now say that. 'The Day of the Doctor', An Adventure in Space and Time, Peter Davison's lovely film, 'The Night of the Doctor'... all the stuff we did was brilliant.
"We carried off that 50th, we absolutely nailed it. No-one thought we would and we did, and it was great and I'm incredibly proud of that. It was hell [at the time], it was living hell, but it turned out great."
And while we'll be sad to see him go, Moffat insists he's feeling "fine" about leaving Doctor Who after so long.
"I haven't experienced the melancholy, partly because I'm still on the job, still doing it, and the other thing is, honestly, when we stopped shooting the Christmas special... I hadn't known how stressed I'd been since 2009.
"When that all lifted from me, I just thought, 'I don't feel like I've got my head in a vice anymore!' - I'm not scheduling my entire life to death, in order to be able to do the work I've got to do. So at the moment, I'm just quite happy.
"I'll be sad, I'm sure, in the future, but right now, bloody hell, is this how the rest of you live? How marvellous!"
Via Digital Spy by Morgan Jeffery
