As promised, my cursory analysis of Japanese-ness of new rival names. Here they are, with their Japanese spelling (the order is given name-surname in English and surname-given name in Japanese)
Sumire Saitozaki 西戸崎 すみれ
Kaguya Wakaizumi 若泉 かぐや
Moeko Rakuyona ??? 萌子
Honami Hodoshima 程嶋 保奈美
Sumiko Tachibana 立花 すみこ
Ritsuko Chikanari 近成 りつこ
Ai Doruyashi ??? あい
Teiko Nabatasai ??? 禎子
Komako Funakoshi 船越 駒子
Chigusa Busujima 毒島 ちぐさ
Sonoko Sakanoue 坂ノ上 そのこ
plus the protagonist: Ryōba Aishi 愛氏 良馬/猟場 (I assumed long o, as there is nothing for Ryoba with short o)
Keep in mind that Japanese given names can be spelled in multiple ways (often dozens), I just picked something.
I haven't found any interesting meanings or references in those names, they seem random.
Also, I haven't analyzed any other 1980 student names, and but I already know some of them (fucking Ui Tunesu) are completely rétarded.
Now for the issues:
- I'm only guessing that Aishi is spelled 愛氏 so that it means "the clan of love", fitting the lore. But surnames don't tend to end in 氏, especially since it collides with using 氏 as a generic neutral honorific. Also, Aishi is not actually used as a name, especially since it can mean 哀史 sad story, 哀詞 condolences, or 哀詩 elegy.
- As for Ryōba, 良馬 is more usually read Ryōma or Rōma, and Ryōba 猟場 is actually a surname.
- There is a female given name Rakuyo 楽代, I haven't found Rakuyona, and -yona doesn't sound like an ending of a Japanese surname.
- There is a surname and placename Nabata 名畑, I haven't found Nabatasai, and -sai doesn't sound like an ending of a Japanese surname. Nabata-sai 名畑祭 means "the Nabata Festival", as "the festival that happens in Nabata", but might be also a misreading of Nabata Matsuri 名畑祭 or Nabata Saiichi 名畑祭一, which are valid full Japanese names.
- Doruyashi is a total nonsense. It's not a surname, it's not a placename. Japanese surnames rarely begin with D, and most of those start with Dai- or De-. The only thing that comes to mind is ドル椰子, a dollar palm tree: