I like how the app Procreate has implemented their Quick Menu. It is fast and easy to pull up. Users can assign their preferred tools to the different slots in the menu. I would love a gesture-activated Quick Menu in GoodNotes. It can speed up my workflow to a great extent. I would enjoy the process more too because I will no longer have to stop to reach for the tool that I want or to go through menu options. The process becomes faster and more intuitive without interfering with my train of thought.