One of the few things that I dislike, is that when i’m doing math problems taking several lines/pages for a single question, I have to always click the "+" button to add pages. It really stops me in my track.

My suggestion is that Goodnotes adds a way to always have 1 or 2 blank pages after the page you’re writing on, if it is the last one. This option would be a toggle you’d activate in the active document’s settings to prevent unwanted behaviours to other documents.

Unlike other suggestions wanting infinitely scrollable pages, it would keep the active template.