@mitu Thank you for the thorough, long and very helpful reply! It is a little clearer to me now. I think it is very likely I will end up with duplicate controllers; there are only so many of those USB controllers, and you can't muck with the ID's. I suppose I could make one, but that seems excessive.. However your comment on scripts really makes me think! It wouldn't be all that hard to hook up something like an RFID reader and attach an rfid tag to the controller panel, and have script selection use that. Pretty minimal code really, once I hassle you all for the general nature of the scripts :)
TBH though, my inclination to older arcade games makes me think harder to attaching a PI 3 to each panel, and just plugging in HDMI/power/sound (maybe a custom connection?). I mean, if I could actually buy them. A PI is actually less then a AAA game. But then you do have to maintain them all, etc