I designed a custom PCB with SMT components, which means no need for a separate break-out board for the DAC, and an on-board switching voltage regulator that provides much steadier and more reliable power for your Raspberry Pi from a standard 9V effects pedal power supply. I also moved the contrast trimmer for easier access, and added a breakout for the Pi's serial port to allow connection via a USB-TTL serial console cable, or even a possible future expansion to add 5-pin MIDI ports.