Gregory's Servera) Good.
b) But then what's the point of the browser-based UI?
The advantages of a browser-based UI is that 1) they can be distributes from a central server, 2) they're quick and cheap to reconfigure and extend and 3) they can save on UI real-estate since the I/O can change depending on context.
1) isn't relevant here, and if you're making a physical button version of the controls _anyway_, neither is 2 or 3.
It just seems like an odd choice (to put it mildly).