So, yeah, I don't have time for all of this ... 

But at least I have fixed a solution for power management : a single "drone" 7.4v NIMH battery, with a 6v / 20A regulator. I looked for many solutions, I think it's the simplest / cheapest compliant one for know. We will see...

I know also that I will start to drive it with an ESP 32 MCU (TTGO D32 Mini boad) for the first version. It will be probably a more advanced SBC for the final version (not necessarily a rapsberryPi)

I cannot promise to work on it in the next few months, because I have no time, and hundreds of projects to work on (yep, I started too much things in the same time) ...