Look Ma, no AC cord!
This may end up being more a proof of concept than final product, but it meets most of my criteria.
Totally self contained. Were it not for the USB keyboard, everything is operational while inside the case.
Everything can be removed and sited adjacent to a larger system, without the case and lid in the way.
The modules can be just as easily powered off a 4ms row power unit, or, standard AC/Meanwell cords.
Unlike the Pulp Logic and Trogotronic cases, this retains all factory Pelican weather/waterproof features. I can bring this anywhere.