Agree. It is too complicated.
One day I saw that supercaps are cheap. And it was the original cause.
I chose supercapacitors because I had inertia of thinking over some radio circuits phase noise and low noise DC. It looked for me that noise wise that capacitors are better than batteries, batteries are better than photoelements, photovoltaics are may be better that references inside the linear supplies, etc.
The hypothesis was DSP wise, that DC source noise is a phase noise of Zero's Hz generator.
So by not looking at role of noise in ratiometric AC I overbuilt the noise defenses.
It is "volt nuts" in bad way. Or design rabbit hole.
I had so many mistakes. But I am glad I that I tried. I still have better ideas to continue all over.
One idea is to overcome few limitations of this DSP chip and use semi-analog approach in phase detector to reach super high resolution on phase.
Instead of digital multiplier, use MDAC four quadrant kind, and go to low MHz. May be up to 10MHz with no FPGA or even DSP.