Just to let you know, the project is still going. I just had to finish a university thesis. Also, the SNES DRONE is now officially my next thesis, which is good because it gives me much more time for this.
As you can see in this picture, development hasn't stopped either. I have control over four oscillators now and at the moment I am working on the GUI, which will be controlled by SNES joypads.
The software is available as a ROM file (even though you won't be able to use potentiometers, duh): https://github.com/hirschmensch/SNESDRONE-emulation
The revised hardware will go into production in june, maybe then I'll have some schematics for you.