Cool, I had the insane idea to have an fx loop for each channel so I could tailor my pedal choice for the best results. I would have to sit down and figure out the logistics.
If you ever do a V2 with the clean channel I would definitely pay for the gerbers and enclosure specs. This build is an excellent example of keep it simple.
I can whip something up when I'm home later as I'm in the planning stages of doing this and adding a CE-1 preamp to make a psuedo CE-1.5 Chorus Ensemble.
C2 isn't in the direct audio path so an electrolytic should be fine, if you don't think it is right you can change it out for a tantalum. Hell it looks like you have enough room on the board to fit a current production film capacitor there if it floats your boat.
You could make the Gear toggle switch a footswitch to have a pseudo 2 channel pedal, using the FB loop on as CH1 and FB loop off as CH2. Almost like Crunch and Distortion on actual amps.