I’m pretty used to how Adobe programs zoom, by now. So it’s a bit jarring for me to switch to Glyphs, where the zoom behaviour is a completely different paradigm.
So I would like to suggest having (at least the option of) zoom that behaves the same way.
In Illustrator, InDesign and Photoshop, when I press cmd-space and press the mouse/trackpad down, the view pans in or out smoothly when i move the mouse/trackpad finger up or down.
In Glyphs, I do this and it draws a square which would demark the zoom region I want.
There is another way in glyphs to get this kind of zoom, but I never remember it.
I don’t know how this relates to apple UI guidelines, but in my view Adobe sets the standards these days, for better or worse, it’s just what most of us get used to.
Otherwise, as always, thanks for a great program!