This project is fascinating!
Thank you for sharing it.
I have one technical question: Would it be possible to add an "active power-factor correction (PFC)" section at the AC mains input?
The advantage of adding active PFC is that it provides increased efficiency and reduces the peak input current taken from the AC mains source, especially during initial start-up.
There are a large number of inexpensive IC chips available for PFC circuits. In addition to the PFC IC chip, this circuit requires one power inductor, one power diode, and one power MOSFET.
Essentially the PFC is a switching regulator of the "boost" "step-up" variety which raises the instantaneous AC input voltage up to the desired voltage for the main filter capacitor energy storage device. The PFC circuit is positioned between the AC mains bridge rectifier and the main filter capacitor energy storage device, which is typically a large capacitor, 100 to 200uF, rated at 400V.
In contrast a traditional diode bridge connected directly to a large capacitor will conduct only when the instantaneous AC input voltage is greater than the dc voltage currently stored in the main filter capacitor. These short pulses of relatively high current cause noise on the AC mains and also can "clip" the peak crest voltage of the incoming AC mains so that instead of a pure sinus shape it will resemble a clipped sine wave.
Best regards and good luck with this project!