Several things that i consider will give a better experience for the user, consistency/coherency and overall better experience with both: Tracks and Lanes.
Reordering Envelope Lanes:
Envelopes Lanes and tracks to similar behaviour on setting height
Notice: while dragging the tracks are expanded and we can preview how they will fit after setting new height. Edit: and both envelopes and tracks can be resided together
Compare with reaper in which this does not happen:
Reaper just expands after setting the new height, which in practice when we are adjusting the height we can't know if it will fit the real state we need for the job .. surprisingly lanes have the desired behaviour tho:
Edit: also both envelopes and tracks cant be resided together
Allow select multiple envelope lanes:
Allow remove multiple envelopes lanes: