Thanks Lugia,
from what I understand the rackbrute cases are aluminum with a bit of wood on the sides (amazing vintage optics?).
After some consideration my mind wandered off from moar modules, to... playing.
Twisting knobs and playing theremin won't go together very... um... melodically, right?
Is an expression pedal module worth consideration?
I would rather not look too much into guitar pedals as an fx alternative (researching modular is enough).
Do you use your theremini as an cv source?