Well, jeez... That's going to be one disproportionate cab. That CP is going to be inmense man... Just remember that you'll have to be sitting down to play the Aero City, just imagine how much room you are going to need to be able to have 4 people sitting down? I would encourage you to consider your design, especially with this being a candy cab.
You are compromising some sort of practicallity for playability. There is going to be so much stuff cramped all over the CP that it is going to be almost unplayable.
I would think that a smarter route to go would be to have modular control panels that you can swap out at any time. Using molex connectors to quickly plug them in and out would be simple to use and that would keep the playability level of the cab.
As for interfacing the contols, I believe the best way to accomplish such a task would be to hack some PSX pads, and use them with various adapters. I believe there are some for XBOX, DC, GC, and PC.