katz,
If you think you might need that many switches, then the MFC-10 is the best midi foot controler out there to date IMO. But it's expensive. And it's a bit tricky to program. Robert Mueller did a nice job on a writeup that takes you through the whole setup process step-by-step. He uses it with a PSR-9000 but it'll still give you a pretty good idea. Check it out http://home.a-city.de/robert.mueller/pdf/MFC10-E.pdf
ev