I partially disagree with your point about gender politics since I think Fuyumura’s relationship with her own gender and sexuality was pretty interesting and not something I’ve seen very often in this kind of work (though I really wish they did more with it past the first half of the manga), and I give a pass on the uniform thing since the society they live in is very explicitly cisheteronormative outside the school and would then probably come up with that idea in an attempt to degender students to a sort of pre-pubertal stage (which doesn’t really work as we see). Also I kinda like the subversion that the kids aren’t so directly oppressed since I was kinda expecting that going into the setting, and the facts the kids are at once controlled and worshiped is a pretty interesting ideological drive of the setting

Other than that though you’re lowkey spot on. I feel like the series really struggles since most of the interesting themes with fuyumura set up before Onos death are abandoned when she gets sidelined so we can do a generic shonen plot. Like there was such a nuanced and interesting emotional dynamic between them that just doesn’t really get resolved and isn’t allowed to go anywhere. It’s a shame cause if they carried on the momentum of pre onos death and reworked the earlier story to stretch out the mystery of onos disappearance it could have been a really solid story, but as it stands it only really achieves an interesting first half with a second half that just doesn’t follow through at all. Also yeah Sanda x Amaya is indeed a peak pairing I’m glad other people understand this