I've decided based on technical specifications, power consumption, and form factor, that the Pine A64+ with Integrated WiFi and Bluetooth was the best choice.

I've pre-ordered it for a little over forty dollars, and it's scheduled for delivery by May.

Meanwhile I may have found somebody to write a UNSC-themed low memory OS for the Pine. If anyone still wants to work on it, drop me a line! Once I get the model to scale with my hardware, I'll upload pictures.