Wow, this is kind of crazy - I wonder how it sounds. The all-BJTs thing is pretty funky and interesting but I'm looking at this and thinking 1) can you just use op-amps in the analogous configurations for the input and output stages and b) 6x linearly-biased CMOS inverters for the distortion stage? That might sound really nice once they start to overdrive.
Glances at breadboard...
I stand watching the steam-liners roll by...