I actually had a marmitey reaction to the story as a whole inasmuch as I didn't like the first episode much, which I felt was clunky and moralistic, whereas the second episode seemed a little more subtle and less preachy, despite the story basically ending with the Doctor preaching. I do feel these type of stories work better when pitched as allegory rather than realism, because in real life you can't end a war by giving a speech.

Thanks for pointing out that Osgood transcends her previous appearances here to become more than just a fangirl, which hadn't really registered with me, but is completely true.