Well, I couldn't find enough time to make a demo video before the prize deadline, although it's not nearly finished, I'd have liked to show at least what works. But so it goes with side projects. Maybe I'll get to it this week.
Looking forward, I'll be ordering some body v1 PCBs soon. They always take a couple of weeks to arrive, so in the mean time, I'm going to focus my attention on the firmware again.
In particular, I need to get the I2C communication with the head module going again. I had it working with the i2c_tc library, but that lib does not play nice with the Audio library. Since I'd like other people to be able to use this firmware, I'd like to avoid build system hacks and library patching. Therefore I decided to use the default Wire library instead. Unfortunately I implemented heavily on the non Wire compatible features of the i2c_t3 library so porting it requires some refactoring. Switching to the default Wire lib will likely help with the search for a new display library. Moving away from SPI means the current TeensyView lib is no longer an option, and it's likely that a replacement will expect the standard Arduino Wire interface.
I also think it might be a good idea to re-visit component sourcing. In particular, the guitar parts themselves. It's difficult to provide clear build instructions without a BOM. I'd love to find a good cheap source for unfinished body and neck parts that don't require having a CNC (or professional woodworking skills). I've also been experimenting with the viability Velostat FSRs beneath wood veneer, which opens some new design possibilities. More on this later.
If anyone is interested trying this build themselves, let me know!