Although the zoom tool is great, I don't use it much. I find that it takes up too much screen real-estate while I'm on landscape mode (which is my preferred iPad orientation) while taking notes. Personally, I would use the zoom tool and find it much more ergonomic if the screen was split in half vertically with the left side showing the entire page that can be zoomed in or out of, and the right side would serve as the space for the zoom tool window.

I hope you consider this suggestion GoodNotes team. It would be a game-changer for me and many other users!