Q1 can be Silicon for less noise. The Page 1 Bias control is good. The gain control on the Fuzz King is good. You could put a 3-knob Tonebender tone control onto the Q3 collector. So I would have the Page 1 bias, the Fuzz King gain, and maybe a tone control. I should do a schematic for that.

You set the Gain for the amount of distortion, the Bias for the quality of distortion, the tone to suit your amp, and there you go. A generic late '60s British overdrive/fuzzbox. You should be able to cover the Yardbirds and early Zep territory anyway.