High speed routing!!
I connected everything up to the Mu. This sucked. Things kept overlapping and it was so bleh.

I started in the top right with USBC and worked down and to the left.

Well. I actually started with the m.2 because they are right next to the Mu, and then went top right to bottom left.

It was at this point that I felt like something might be off. Why would the pins for one HDMI port be backwards but not for the other?
The answer was simple: I had the pins wrong. Oops.
Once I fixed that I could line up everything real nice.
But first, after a tip from a friend, I dropped the USBC lines down to the bottom layer so that everything else could be top. This made it so much cleaner looking.

SO much better. I am a little worried about EMI from the buck converters but I think it might be ok? I’ll add a bunch of GND vias or something.

After I had those all wired up, I did the last few small circuits.

LORAWAN.

GPS, with the antenna keepout.

The power switch.

The fans.

And last, but certainly not least, the CMOS battery.

And with that, all the individual circuits are complete.

So what’s left?
I literally just have to connect all the low speed lines up to the Mu, and I am done. This is no small task, as I have to weave around and through all the high speed lines, but it is very possible. It will get done soon.