Thanks to OSHPark the boards got here quickly, but I'm still waiting on some parts like the regulator, to populate the PCBs. I noticed that one of the resistors seems unnecessary, I've copied it in from the 5V design and forgot to remove that. Maybe I'll put a pull-up resistor on the reset pin in its place - although I do believe there's an internal pull-up resistor anyways, albeit weak.

Someone managed to order and build this project before I even had the chance to solder something together! Turns out there was a minor mistake in the design where two ground plane fills were separated. The V-USB firmware is reported to enumerate - yay :)

@davedarko cool board pic.twitter.com/cHx3ow6cYf
— Dan Watson (@sync_channel) May 23, 2020