It would be handy if you could label a whole video/audio track so that you wouldn't have to label/relabel your clips every time you move it up or down a track. This would improve workflow for some people who are visually editing/organizing clips as they don't have to keep checking which color is which track.
The tracks would obviously stay like they are now but you could right click on the track you'd like to label/color and change it via the "Customize..." option.