I have not built this yet, but had the idea to replace the comp, gate, stab with wah/expression pedals wired to the board in place of the pots. Has anyone tried this, it would be so freakin sweet, impractible but sweet none the less. ;D
You could definitely do it, its just super offboard wiring essentially. May get some issues with the value of pots in the expression pedals though. I think the real problem though is the fact that you will probably drive yourself out of your mind since it'll be even tougher to control the pedal's characteristic oscillations and feedback
I think an even cooler idea to me, would be to wire up the OPTION to use the expression pedals but leave the pots on to work as usual if there is no exp plugged in. It'd be adding a lot of extra jacks to fit in your enclosure but you seem like you'd enjoy the challenge ;)