When do handwritten notes direct on a landscape oriented page (in big paper formats like A3) there is no room on the right to scroll out of the page, having enough space that my hand stays on the iPad so that I can continue writhing.
Example: When you use a horizontal A4 page and zoom in that you can straight write on the page you can move the page more and more to the right while you are filling the paper. Once you are reaching 2/3 of the page you can still continue scrolling right and there will be this gray area but you can continue writing. On horizontal A3 mode this is not possible and you have to continue writing with some very awkward hand posture.

Suggestion: having enough room on all pages sizes and orientations next to the page itself to enable writing on the whole page while having the hand on the iPad (see attached image as problem description detail)

Using: GoodNotes 5 on iPad Pro 2020 12.9 inch

Thank you! I love this App and only this is the reason why I took the time to write you :)
— Stephie

PS: Sure I have more ideas: Some Whiteboard-Endless Canvas would also be nice because then I could draw as big as needed images for anki flash cards or in my psychology study lessons. But one step after the other - for now I try to overcome this with the usage of very big page sizes (like A3 in landscape), but with that no-hand-space problem, I described above, my work-around solution is suffering.

Stay healthy!