Command Panel should be a bit smarter and detect when there is space available on 2nd Panel with the double-width configuration.
Scrollable section of 1st Panel should detect and make use of available space on the 2nd Panel
When there's one section that you have to scroll through, it should wrap around or "right justify" to all that real estate available on the left on 2nd Panel.
Rollouts sections on the 1st Panel should auto expand and if make use of the 2nd Panel when this is empty
There should be no need to manually expand each of the rollouts to access their content and have an optimal layout. with double width configuration of Command Panel.
2nd Panel should auto collapse into one when its not needed
When 1st Panel has enough space to display the Command Panel Rollouts, Parameters, List sections etc. 2nd Panel should collapse into a single width display.
Fix the unpredictable behavior of two panels turn into a single wide one
I usually work with two panels, but often times and randomly the 2 panels turn into 1 big wide panel for no apparent reason and I have to stretch and squash it around until it returns to 2 panels. This happens with the data channel modifier (depending it seems on the inputs you have active), and consistently with the path deform (non-WS version) and chamfer modifier (check the 2nd image!)