Still miles behind some of the professional work seen above, this was my original panel from 2008.
NOS LS-30 for Player 2 and a Happs Mechanical Rotary for Player 1.
3 inch Happs Trackball and a Slickstick Tornado Spinner, along with a standard 4 Way at the top in the middle.
I'm big on left hand and/or right hand friendliness along with adequate distance between player spacing.
During Arkanoid, for example either of the red buttons next to the trackball serve as the P1 fire button in conjuntion with the spinner making it both Rh and Lh friendly.
I have another 21" crt and am working on a double stack monitor setup (think Punchout), but with an optional vertical orientation for the top monitor.
There is also an additional,modular, single monitor stand to support side by side monitors side by side for spirited 2 player simultaneous action.
I am considering a trigger stick for the area to the right of the Spinner for the standard Tron Setup.
I only recently broke out the router and routed the bottom of the panel for the 4 way and the player 1 rotary joysticks.
The top of the panel was routed for the track ball mounting plate as well as the top mounted wooden plate for the SNK Rotary.