[werk_ag]

That's true, I was worried that it was going to be too complex but once I started assembling the breadboard I was surprised it was fairly simple.

The Eagle scheme gives the wrong idea, I did it just to draw the board and did not think much in the aspect of making easy its interpretation. Luckily, with your drawings you did an excellent job dismantling this apparent complexity.

I have skipped the switches and jumpers that I will add in later (once I discover what they do ).

Being at this point, I will not spoil your enjoyment of discovery ...
Soon you'll be seeing those data in Cumulus!