2. Death. For Real.
Here's one that might be completely right, or completely wrong - and either way,will be divisive. Steven Moffat has certainly attempted to take Who in a dark direction, personified by the change in the Doctor himself, over the last few years. Just how effective this attempt has been...well, that's up for debate. Yet, one storytelling element that even Moffat has avoided is death. In fact, the dial has been spun in the opposite direction in every case. Not only do the Doctor and his companions not truly die, they live hundreds of lives (Clara), fake their deaths (The Doctor himself), or live out their lives having been transported by Weeping Angels (Amy and Rory). Even in the Series 7 finale, technically dead characters found themselves completely revived before the end of the hour. One way to restore both gravitas and danger to the show would be through the legitimate and permanent deaths of characters. This isn't a call for widespread slaughter, but it seems to me that the idea that actions have consequences has been lost in some ways during the last few Series of Doctor Who. Reintroducing the ultimate fact of life - death - back into the equation could help bring that idea back into focus.