YummyFuzz,
The ratio of R3 to R2 will set the gain of the first stage. If you keep them the same this stage will have no gain (unity).
R2 contributes to the input impedance of the pedal, so raising this to 220k (or something relatively high) will help it work better with other pedals and guitars. As you noticed, version 8.2 has some changes that uses a different topology to raise the input impedance very high, as well as a quiet switching circuit that keeps the relay click from being heard when the bypass switch is pressed. If you want to play with the first stage’s gain, I would suggest replacing R3 with a 500k trim pot. This would give you maximum gain of over 2, which is probably too much…the later stages in the circuit might start clipping, but you can always dial it down. There’s no need to use a trim pot in place of R2…it’s best to just keep this as a set resistor.
Hopefully this answers your questions and gives you something to work with.
Good luck.
-Brach