NLA Groups to allow multiple edits for multiple animations

The NLA editor is great for layering animations together, but it comes with a major limitation. If you were to combine multiple action strips into a composite animation (idle_base, idle_secondary, idle_poseAdjust, idle_hands), they are stored explicitly on the track, and only one track is active at a time. This limits your ability to have multiple animation edits for multiple animations. What if you then wanted an NLA composite of a run, built out of run_base, run, secondary, run_spine, and run_Yforward? You have three ugly options:

1. hide all the tracks of your carefully crafted idle NLA animation, and turn on all the tracks of your carefully crafted run NLA animation (tedious)
2. Use a different scene for every NLA animation composite you make (unwieldy and error-prone; can't see animations easily next to one another, and might make a change in 1 scene that impacts the 2nd scene)
3. Bake the NLA strip down to a finished animation, then delete all those action strips and start working on your next NLA animation composite (destructive; you can't go back to the NLA edit)

My proposal: Groups! Here's a mockup. This would let you have all your beautiful Run work in a group, all your beautiful Idle work in another group, and it'd be one toggle to view the whole thing on or off.