Ya'll may also want to check out Midori¹, a favorite of the journaling community. There's also Northbooks², a small American company. And Nanami Paper³ if you want to try out quality paper in the ultra-thin direction.
[1]: https://md.midori-japan.co.jp/en/products/mdnote-cotton/
[2]: https://gonorthbooks.com/
[3]: https://www.nanamipaper.com/products/cafe-note-b6-slim-grid....