4. Everyone Is Glib
Doctor Who, once so eccentric and British, cheerful and earnest, grumpy and sly, has become somewhat infected with one of the worst tropes of American TV: the constant wry asides. Moffat has always been a witty writer. He has a host of sitcoms under his belt (Chalk, Joking Apart, Coupling) and knows how to write dialogue that pings. However, while a cool one liner is fine and dandy every once in a while, and the Doctor is supposed to be funny and smart, the show is also supposed to be, at its core, a show about the dangers of time and space, monsters and lasers, difficult choices and running. It's hard to create stakes if everyone's so glib all of the damn time. Your average scene in Moffat's Doctor Who Who goes something like this.
INT. SPACE STATION Clara: Where are we, Doctor? Doctor: A Bandarian Cruiser (presses buttons on a console) Excitable witty remark. Clara: Are we in danger? Doctor: Witty remark, play on words. Clara: Exasperated witty aside. Doctor: Pardon? Clara: Nothing. Witty remark under breath. Doctor: Good! Eccentric shout, undercut by witty remark.
Not only does this have the effect of making all of the characters sound the same, because everyone's the clever-clever funny one, but it also makes the show seem impossibly smug. Try introducing a friend to the show as it stands now and they won't like the characters because they're rendered so often dispassionate by their almost psychotic levels of lol-banter. Say what you want about Russell T Davies, but at least he was always earnest.