If you are concerned with baffle stiffness why not double up the thickness with a baffle sandwich.
Add a front panel, mirror image of your current design (minus the terminal cut outs) would leave a nice clean finished look.
Rubber sheet gasket in between the two layers and you may not need the slight driver recess.
Choose the gasket material correctly and you may not even need the 100 driver mounting screws.
Twenty bolts from the backside should hold the panels together and keep the that nice clean look.