More than any arrival of a companion since Amy, Clara's arrival has signaled a sea change for the show, particularly in the writing. Where generally a series of Who lately (other than 6, which was known as "the one that Neil Gaiman wrote and everything else"), the writing has been "the ones Moffat did", thus far the second half of this series has been brilliantly written, and we STILL have a Gaiman and a Moffat episode left to go. But there's overall in the show, I don't know...it's still Doctor Who, but it feels a bit more modern and a bit more, I don't know, mature? Especially Hide, which was downright brilliant.
Incidentally, I'm amused by the fanboys who think the reveal of the last episode's name thinks that means Moffat is actually going to reveal the Doctor's name and are furious. There's no name any writer can come up with that will meet decades of expectation, for one thing. And for another, at some time, River learns the Doctor's name, and thanks to the fake out in The Wedding of River Song, she still doesn't know it as far as we know. Far more likely that the series finale shows her finally learning it without us HEARING her learn it.
"More than any arrival of a companion since Amy..." whuh!? Amy, Rory, Clara - who else?!
Aside from that, though, I do sort of agree with you. Series seven, so far... it's been a show I like, but not the show I love. Rings was interesting but a little ropey, Cold War was solid but not exceptional, and The Bells of Saint John was a great episode, but not a great Moffat episode. Hide has transformed my opinion of the run practically overnight, and is starting to hint at similar greatness to my favourite series, S5.
Because, honestly, it's all there. For all they said that they were dialling the arc right back, it's actually starting to look present, but a little more
even. Series six was built around the Moffat episodes. It was a bunch of really arc-heavy episodes; big, cramped adrenaline rushes where all the plot happened, linked by episodes full of cliffhangers and cursory nods, but without development.
Here, however, and Hide is the first time this is really coming to the fore - the TARDIS stuff is growing, Clara's relationship with the TARDIS feels like part of a bigger story. We're learning more about her, we're seeing the Doctor develop, we're seeing the Doctor's suspicions laid out, we're seeing her reacting to time travel. It feels like we're edging forward with each episode, and the mystery is thickening, and layering, and advancing gradually, just like it did in series five.
Little details like that can make or break a series. Rearranging three episodes in series six, I think, made an already slightly problematic series seem clumsier. There's a lovely moment, at the end of Night Terrors, where the Doctor says, pointedly, "Here we are, together, in
the flesh," and it would have originally led straight into The Rebel Flesh. It's him voicing a suspicion, and it would've made his odd behaviour in the following episode more intriguing, and we'd have been speculating, and it'd have hinted at the Almost People cliffhanger and rewarded the eagle-eyed viewer. As it is, the foreshadowing was broken, and they crammed a few 6A elements into The Curse of the Black Spot. 7A felt a bit weird, too, because it was sort of a coda. The Ponds didn't rejoin the TARDIS full time, so it was more like a very slow departure than a big, fun adventure.
Hide feels like the show I adore - series five, full of beans, arc rolling on, interesting characters, and yet also brand new. I don't think S6 was a bad series at all, I think the arc was done badly, but the series was great. And it works retroactively, because I can now see a story being told slowly, one that's starting to take shape, and so the last two episodes are taking on clearer shapes, too. I'm incredibly excited about next week's episode. I can't wait to see where I'm going. It's taken a few weeks longer than I expected, but I'm a proper, card-carrying, giddy-as-a-babe Doctor Who fan all over again. Terrific.