If anyone is interested, I've come up with a universal Arduino / Mozzi development board, all open source and some test code:
Schematics and build files so far there's some code for a 5 note poly synth, a noise maker etc.
The board can be configured where all the Arduino analogue inputs are connected to 8 potentiometers, or you can link a header out and introduce a multiplexer giving 16 potentiometers. Hardware configured for the #HiFi audio output, and also has a Midi In port, and trigger in port as well as 5 toggle switches.
I have a couple of boards left over if anyone is interested or you can just send the manufacturing files straight to JCLPCB or Elecrow if you want to make your own.