so you will basically just be 3d printing a plastic enclosure? (which if you want >10 of could probably be done better quality for cheaper overseas)
then youll simply connect an RPI, PSU, and 'chips'? "chips" require control boards and software, as well as power delivery. its not gonna be some GPIO attachment for an RPI. What about heatsinks? fans?

If building a miner was this easy I would have built it already, but without a plastic housing that obstructs airflow

ps: GUI requires 'interface'. Are you saying that you'll be building a touchscreen into the front of the unit? I think what you meant was a small status LCD or a panel of LEDS.