Change the nub to an analogue stick.
here's the challenge though, I'm not actually designing this, I have no money invested... JXD is, and they're not going to dump a whole lot of money in development into just one device. I'm really confident they do however want to work with me to get something out to the retro gaming community, that was my main spiel when I started talking to them about what demographics they're going for and what not, and I think that's the only reason they're paying attention to me. So what I'm going to have to do is to have them re-use stuff they have made before... just in the right combination that will work for us, not actually design anything new. They want cheap, and they want fast out the door. Little R&D dollars as possible.
also as an update it's too late for the S601, they're already moving forward with the original design and had been since I started talking to them, "too late to make any changes to the model now" but they're looking for ideas for the one after this one.