First off, what boards are out there that are ready to accept data and translate it into MIDI or USB to feed straight into your computer? This is an important piece for me, as I would rather spend my time figuring out the design and control surface than the programming and firmware and blah blah of building a PCB. Well, there are those that work for joystick, keyboard, more gaming-centric controls:
http://www.create.ucsb.edu/~dano/CUI/ - VERY free form, not sure this is for me
http://www.leobodnar.com/products/BU0836X/ - close and has quite a few controls
http://www.ultimarc.com/ipac1.html - again too much for gaming, will literally make your PC think there is a second keyboard. Could be interesting for a future application.
Or jump direct to the very few who’ve built a device specific for music apps:
http://www.doepfer.de/ctm.htm - MIDI only
http://www.doepfer.de/usb64.htm - with USB, but very pricey
http://www.halemicro.com/Products/Products.html - UMC32
http://www.audiomulch.com/midipic/ - good luck here if you aren’t super computer programming savvy.
If going the joystock/gaming route, the main advantage seems to be price. I can’t think of much else, although it may also be a little simpler. I recently saw a you tube video here: http://www.youtube.com/watch?v=NAosgd9Cy6U - that does just that. Its incidentally a good tutorial as well, and plays to a couple similar ideas I have for my controller (such as the arcade buttons).
Going the route of MIDI/USB appears the way to go. The Doepfer controller is what I found first. I skipped the CTM because its MIDI only, and I wanted to have USB. The USB64 is actually what I originally decided on, but it is VERY pricey. Its carried domestically by analogue haven and probably a couple others.
But then someone referred me to the UMC32 by Hale Micro. Its an unknown and has half as many control points - BUT its less than one third the price of the Doepfer, and the guy who builds them (his name is Ken) was immediately responsive and helpful. He offered tips and advice, offered discounts for bulk, etc.
In short, this is the one I’ve decided on, and have begun designing the schematics and control limits with this device in mind. At present, intending to purchase 6 of them and chain them together using a powered USB hub (self-powered to prevent low power issues with so many devices sucking juice from a single USB out of the computer).