What is the use of the Harmonaig ? Both Marbles and VB offer quantized outputs, and I feel like such a best of a quantizer would be a lot of overkill for a relatively small build, but I may be missing something...
Also, +1 for Beads but it might be my own desires masquerading as advice.
Pretty good build overall though, I’d have fun with this. Definitely do what Jim suggests, having a look at old plans after a few years can be funny, and even insightful...

--- Voltage control all the things ---