Expose keyboard shortcuts as tooltips in all areas of the OS
For example:
- Hover on Activities button and it shows "Super" as a tooltip, making the user immediately know its shortcut.
- Hover on Date and Time in the status bar should show "Super+M".
- Hover on "Search" button in the Files app and it should show "Ctrl+F" in its tooltip. And so on.
Please look at elementary OS for live examples of the implementation. elementary has done this throughout the OS interface as well as apps, and it's been incredibly easy to learn all the shortcuts! GNOME already is great with keyboard navigation, but the shortcuts aren't exposed naturally to the user. This could help!