The main story is a bit whatever.

That ending though, it broke me a bit I have to say. I really love 8 and Charley, it's a TARDIS team that is probably in my top 5 of all Who media. So it's sad to know there's only one story left (as in canon order, I know they have released more afterwards), and I hope they don't part ways as badly as the last 5 minutes of this are indicating. The best episodes are the ones that put their relationship front and center (Scherzo is an obvious example) so I'm hoping to get some of that in The Girl Who Never Was. Will probably write something there when I finish it (if I don't like it I probably won't tho).