Thank you for the kind words, Triode. I don't have any plans yet as to how I will deal with the developed circuits. They may look simple, but most of the work is in just these simplifications. "Let's make it simple, but not simpler."
The goals were: no warm-up and temperature effects, really good linearity, avoidance of hum, volume range 90 db, a natural sounding overtone behavior without resembling a synthesizer. Dynamic acceleration of the volume for plug and push effects (ADSR) organically by hand movements without manual adjustment. The right geometry of he antennas, air wound coils are fundamentally important.
Some ideas have stayed in my head to this day. Yes, PCBs are possible, but solid free wiring is also an option for me to celebrate visibility and simplicity. I need time to write down all thoughts and decisions I have made and those that have failed.