6. Complicated Overarching Plotting
A series of Doctor Who is always quite a strange beast. They're comprised of individual episodes, mostly written by a different writer, often featuring a completely new setting, cast of supporting characters and even sub-genre. It's Freak of the Week-style plotting and it requires deft control by the showrunner to ensure that each episode is allowed to grow and flourish as its own journey, while also feeling part of a wider narrative, something to give each series an identity of its own. Russell T Davies was good at this. Bad Wolf, his first arc, being a particularly strong example of a recurring narrative plot thread creating intrigue throughout a series without damaging the component episodes. Steven Moffat lifted this template pretty much verbatim for his first series in charge, simply replacing the words Bad Wolf with the image of a crack in time. There were warning signs when the crack acted as a deux ex machina during one of the mid-season eps (Flesh and Stone), but otherwise, a fine example of arc plotting. Things have gotten much worse since then. Series 6's overall narrative concerned the Pond's baby being discovered then born and stolen in the course of two episodes. Then, disastrously, the episodes were shown out of order, so the episode following Amy and Rory's baby being nicked was the one originally supposed to be shown fourth, before the baby drama even began. The Ponds total lack of concern throughout that episode for the whereabouts and welfare of their missing baby completely compromises that episode, which isn't fair on the audience or Mark Gatiss, the writer. Other episodes, like Matt Smith's final episode, were so bogged down in trying to tie off all of the remaining plots strands (who blew up the TARDIS, who are the silence, what is the Doctor's name, what's the deal with Trenzalore!?) that there was barely any time to just enjoy the episode. Stop talking to us about stuff and let us feel things! The next plot arc gets an entry all of its own.