The T-molding does indeed look great, but I just noticed the holes on the side of your CP.
Are those for pinball flippers?
Looks like you'd have to either crank your wrists sharply downward or bring your shoulders so far forward that they'd be directly over the flipper buttons which would put your head really close to the monitor.
You might want to consider putting your flipper buttons about where F1 is below so you can rest your thumbs along the t-molding and still easily reach the flippers.
(Cardboard box test highly recommended.)

If you'd like to re-purpose the holes you currently have, you could use Neutrik
USB feedthrus to allow players 3 and 4 to plug in gamepads. Since normal 1-1/8" holes are larger than the feedthrus need, you can add the associated waterproof gasket in
blue or
black to cover the gap. (1.34" W)

Scott