Beyond the early MacOS UI/UX, I would look at pre-smartphone devices as well. Palm pilot, phones, etc. These will give you ideas on what you can accomplish with lower resolution UI screens.

For that matter, look at good TUI applications... (not the render path, but the result as a whole) ... blocking/spacing and clear controls, etc... though you'll be more touch, less tab/enter, etc. A TUI App renders by characters, but you can still learn from the overall layouts. Simplified menu lists with fewer items in a hierarchy, etc.

If you can and have physical buttons, think long and hard about their functions, especially if you have a limited number... these should do your most important things.