Also, i dont believe it to be interesting to reinvent the wheel. Raspberry Pi is a perfectly cheap solution for running CGminer from out of. It will be much more expensive to have this on each and every board..
Ethernet mac chip for pic32mx7xx cost ~0.99$ (in reel), rj45 socket less 0.5$, some xtal, res, caps etc and ~2cm² PCB area. Say total max 4$. RJ45 socket can leave unpopulated so customer can solder it if need. Other parts pnp machine lay board <0.1s.
One board can act master and chain other 16.
I see raspi ~50$ vs. ~4$ (plus onetime code/firmware generation = port cgminer to mips and some micro tcp stack).
If burning boards are done say 2000pcs and every 16 needs raspi -> 125 x 45$=5600$. I can't say is it enough to modify board now. Atleast it reduce one board + wires when suitable firmware are done.
I see it good option, not reinvent wheel.
A raspberry pi is $25. and its a fully fledged computer running on archlinux, you connect your chain of Bitburners to the USB port, and cgminer on the PI does the work for you.
Where would cgminer be running in your option?
I definetly see it as an option, just not a necessary one for me at all. Especially, when he starts shipping, the difficulty will be way up, and second generation chips would already be taking orders.
Keep it simple!