Well, I’ve got a bit of time at the moment, so let’s go. 
On Nausicaä
That’s basically my feeling too, but I was gonna be a bit ruder about it: I don’t like volume seven. I’ve never liked it, any time I’ve re-read this story. Someone’s gonna say I’m being unfair here, or that I’ve misinterpreted something. I welcome it - let’s have a conversation! 
But yes, in contrast to the journeys and adventures we’ve had so far, this volume essentially just turns into riding, and then chasing, a God Warrior across a desert, punctuated by two extremely philosophical discussions, and little else.
Starting after the sequence with Tepa and the Valley (end of Week 17 in our reading schedule) Miyazaki puts Nausicaä through an absolute wringer, more than he was before. He systematically disassembled everything that made Nausicaä Nausicaä. He’d already taken away her father, and (unbeknownst to her) her home, now, in rapid succession, he takes away her pacifism, her mentor, her cute animal companion, her fundamental belief in the natural world, in some ways her belief in the decency of humanity as a whole (though that one I’m less certain of), and finally put the onus on her to decide the fate of everything.
I mean, one connection I suddenly made on this reading of the story that I don’t think I’d made before was that her path is littered with people who gave up everything they had to follow her - Mito and the other old men who left their home behind fully expecting to die somewhere in the Dorok lands, Charuka who disobeyed his emperor for her, Chikuku who lost everything he knew (though in some sense he didn’t have a choice), the wormhandlers who literally murdered their worms and abandoned all of their worldly belongings - so in some sense it’s only fair that Nausicaä also give up everything, but… why’d Teto have to pay that price?
I read somewhere (though I can’t find the source now) that a lot of the nihilism of the last arc comes from Miyazaki’s disillusionment in the state of the world - in particular, the fall of Yugoslavia in the early nineties damaged his belief that humans could strive towards the common good, and… it annoys me that he couldn’t keep that out of his work. Yes, Nausicaä still hopes for a better future, but it’s less “we can do it!” and more “we’ll make it work somehow”. The fall of Yugoslavia also forms the background to Porco Rosso, which was released in cinemas at about the same time.
That said, also at about the same time, Miyazaki animated the music video for Chage & Aska’s On Your Mark, and some have theorised that the story in the video is a sort of apology for what he put Nausicaä through…
Mind you, I utterly reject the claim by both the Keeper of the Garden and the Master of the Crypt that purification-era humanity would be unable to survive in a purified world. It’s not like a day is going to come when the timer goes “ping” and suddenly all the air is clean. Presumably someday the surviving humanity will travel through the forest to the place where the purification is complete, but even if it is true that humans suffer the same death with too little miasma as they do with too much, there’ll still be a territory inside the purified region where the air quality is about the same as it is outside the forest. And maybe they’d only be able to survive there, but… their children will be able to venture further into the purified land, and their children just a bit further, and so forth. (Though that’s assuming they make it that long - the Master was begging for his life, yes, but some things he said were definitely true: the hardening disease is real, and populations are decreasing.)
But yeah, her rejection of all the knowledge and technology of the Old Ones was a bit unsatisfying. About as unsatifying as the ending of the new Battlestar Galactica, actually - “let’s give up all our lifesaving technology and live in harmony” was supposed to be uplifting, I guess (?), except that canonically, or modern-day world was the outcome of that. But yeah, getting back to Nausicaä, her decision basically boils down to “We’ll be fine on our own, thanks”, except they’re blatantly not fine - Torumekia was already at war with the Doroks before they started using the technology of the Crypt to make biological weapons (though granted it did turn out that the Crypt itself was the Vai Emperor’s primary motivation). Instead we’re left with a slightly watery ending of “We must live”. And to be fair, they still have access to the resources of the Gardens, if they can find the other ones.
Also, granted only three people besides Nausicaä ever heard the name she gave to the God Warrior, why does noone ever comment on the similarity between オーマ and オーム?
Well, that wound up being a bit less coherent than I was picturing in my head.
But for one last irrelevant point: the very final panel is dated January 28th 1994 - if we’d held off the final reading for one more month, we could have finished on the thirtieth anniversary.
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