Firstly, congrats on your design. It is obviously well researched and thought out.
Initially I went down the design path of the dual level CP based on the Supercade design. In my opinion it is one of the most tasteful around....
But you know, I just couldn't make it work even with a similar design as yours. There always seemed to be a compromise between player comfort and that dreaded trackball position. Finally I gave up and just enlarged my control panel.
I am sure you have heard it over & over, but it really is worth the investment in time to mock-up your entire design for testing.
I am interested if you can make it work and wish you good luck, but there does seem to be a lot of controls in a limited amount of space.
Cheers dude,
Bones