Any chance you could share pics? That sounds really interesting and all stuff I’d love to have done to mine.
Is the loop post-envelope detector?
One other mod I’d seen was that the distortion trimpot was given a surface knob so it could be dialled in to taste.
The biggest leap I’ve made in actual keys playing is learning good pentatonic fingerings in all keys. I highly recommend Marius Nordal’s book “Wisdom of the Hand”. I got it and started working out if it at the end of last year and it has absolutely transformed my playing.