Here's a way to get your sounds set up for live use, without using up too much rehearsal time -
Before rehearsal:
Choose just one gain sound to use at the next rehearsal.
Choose just one clean sound to use at the next rehearsal.
If you cannot turn up to rehearsal/stage volume at home, you may have to re-adjust these at the rehearsal space, but, adjust the clean and gain sounds to have a good tone and volume balance, so you could switch from a clean to a gain sound during a song.
At rehearsal:
At rehearsal volume (or stage volume, if it is different), you can make the final adjustments to be sure the clean and gain sounds have the tone and volume balance you need to be able to switch from a clean to a gain sound during a song, and for both sounds to sound right onstage. These are now your two Reference Sounds.
After rehearsal:
Add the other sounds you need.
With each new sound you add, compare the volume, bass, treble, etc of the new sound to the the clean and/or gain Reference Sound.
BTW - If you have to turn down at home, your two Reference Sounds will be affected by the change in volume - that is OK. If you adjust your new sounds to balance closely with the Reference Sounds, they will still be balanced when you turn up for rehearsal/performance (or, be so close to being balanced that only a minor tweak will be needed).