Buffered Stereo Splitter Box

[Raygun]

Hey folks! I've been a on-and-off lurker around here for a while now. I have a bit of a special project I've been working on that I have some questions about.

A little about me first: Hi! I'm Ben from Montana. I've been playing guitar since I was 16 (drums since 12) and I'm 39 now. I have over the past year or so gotten into building my own effects and signal routing boxes. I have built a passive stereo splitter and an 808 Tube Screamer so far, with a couple more projects set to come here in the near future. So I'm not a total noob, but honestly, I am still pretty noob at this.

I have some questions about some somewhat esoteric stuff (to me, anyway!) that I haven't yet found any answers for, so I thought I might as well join up here and throw some questions at you guys and see what happens.

I'm in the process of laying out a build for a buffered stereo splitter box for my guitar, which has both EM humbucker pickups and a piezo bridge, both sent through a stereo cable. Both channels will be buffered with the AMZ opamp buffer built on slightly different circuits. The EM side will be relatively simple; it will go from the input to the buffer to the footswitch (true bypass w/LED) and out. At this point, I have decided to try it with buffer always powered (ahead of the footswitch) in order to avoid any potential popping, and that both footswitches will bypass to a third output going to a tuner.

This is where things get interesting: I would also like to incorporate volume and tone controls on the piezo side. I did this with the passive box I built in order to provide volume matching and offer more than one tone option (as this output then goes to an acoustic modeller), but I'm not sure what the best way to go about it would be with the buffer in the picture. Is there any foreseeable problem with running the piezo buffer ahead of the footswitch and the volume and tone stack after,  then to the output? It seems to me that this would also help eliminate any potential popping without resorting to pull down resistors on the inputs and outputs (as I did on the passive box), but I am not sure how sound the plan is there. The piezo puts out a ton of signal and I have read that tone stacks have a tendency to affect output level (often requiring a recovery gain stage), so what I am hoping that those problems just offset a bit. What would be the best order for the buffer, footswitch, and volume/tone controls?

The other thing is that I would also like to incorporate Jack Orman's AMZ Presence Control (V1) into the tone control (I like the idea of an adjustable mid scoop on a two-pot control, saving a little space in the box), but I am afraid that my Schematic Fu is as-of-yet pretty weak and I am not exactly sure if I have it laid out correctly. I suspect that's probably an annoyingly noob thing to ask about, but any help before I start soldering things to my face would be appreciated!

Thanks for your time and patience.