Create a submix from audio clips, not tracks

I would love to be able to create a submix from specific audio clips regardless of which tracks they are on, instead of from whole tracks. Simply add an output assign feature on each audio clip that would allow the user to send the audio clip to the main mix or one of the submixes. It would cut way down on my projects' vertical timeline growth and allow me to keep more efficient track management.

Thx,

- DK