Hesitant to jump in here as a new user, but new user mindset is fleeting.
I am puzzled why there are two separate keyboard shortcuts for Expand and Collapse:
Control-Command-9 Expand All
Control-Command-0 Collapse All
Command-9 Expand Item
Command-0 Collapse Item
Why not simply use toggle behavior with these and cut shortcuts from 4 to 2? It would decrease brain effort to learn by 50%.
Thank you for considering, and would welcome explanations why bad idea/wouldn’t work/don’t rock the boat/etc.