I've gone through a few approaches trying to deal with this. Here is my current method:
- use VU meter on AxeFX to get close when switching between scenes
- last block in my chain is a PEQ tied to foot controller for -12dB to +0dB gain.
I used to have a "lead" button with 4dB boost but I found this inadequate to manage the variations.
If you are a tight band with a specific rehearsed show then I can see dialing everything down to within a few dB. But if you are a weekend warrior cover band doing a variety of songs, and a loose arrangement with different dynamics each time, then the +4dB IA switch doesn't work. I found that when the whole group got louder, I would kick on that button too early to get my sound up then have nowhere to go up from there.
I tried for a while to have separate scenes for finger picking vs strumming, to account for the different boost needs. I still might go back to this but I'm abandoning it for now because I got a better guitar with more touch-responsive dynamics and I use it to control clean or crunch playing more now, so less need to switch scenes for that.
So my approach now is to dial as close to equal as I can using similar dynamics across all scenes/patches. Then playing live I put the volume pedal about middle position or a little less, set the Main output knobs on AxeFX to desired loudness, and use my foot to fine tune the mix the rest of the night.
This works because I'm not sending to FOH, just using my monitor like a back line and the whole band is physically close together in small bars. It also works because I'm not one of those players that expects to be louder than everything else.