Being able to selectively hide tracks and groups would be a great help in organising session workflows on a small screen. It helps workflow a great deal to be able to keep only what you’re working on at the time in view.
A full implementation would be a drop down/pop out menu with checkboxes to show/hide individual tracks and groups. A simplified version would be toggles for ‘show/hide all tracks’ and ‘show/hide all groups’, although that’s much less useful.
A good feature that goes with this is a ‘spill’ button on groups and output buses, which shows all tracks/groups that route to that group/output bus and hides any others.
Oscar