The Clairefontaine paper used in Rhodia's Rhodiarama notebooks are also excellent. The soft cover Rhodiarama are some of the best paper for really watery inks. Another fantastic option is Midori's notebook paper, their whole design and the open grid option are really pretty. https://www.midori-japan.co.jp/md/en/products/mdnote/ Also if you're willing to over pay, the Kleid 2mm grid notebook with OK Fools paper are among the highest quality I've used. It has handy feature of detachable pages too.