I use GoodNotes for teaching (and it‘s great for that). However I‘d love widgets like timers for students. I use classroomscreen.com for timers and soundlevel sensors, which are oddly specific requirements for teachers. So I don‘t think features like these will be implemented.
If I could use the presentation mode while in splitscreen, I could show timers/other widgets on one side, while not losing space in my GoodNotes document. Also I don‘t want students to see messages popping up on my screen.