1) learn what clean sens does as others have mentioned. Second, figure out, write down, or remember the ideal clean sens setting for each guitar you use, mindful that this may be a compromise if you have, for example a neck single coil and bridge humbucker. Until this is set correctly, it is a waste of time and counterproductive to try to balance all your rigs.
2) utilize performance mode. The beauty of the default "crunch" rig that loads by default in a new performance is that you can volume balance all the Rigs you bring into this performance to this reference. This avoids the "telephone game" effect. (You balance rig 2 to rig 1 , a week later rig 3 to 2, then rig 4 to 3, then Rig 5 to 4 and so on. Then you realize that Rig 5 and 1 don't match.) By always balancing new Rig to the same default rig, minor inconsistencies in how perfectly you match will be minimal.
3) Make necessary adjustments to the amp volume not Rig volume. If you discover you needed to lower the volume of the amp, (say from 5 to 4.6) save it. Then go to browser mode, find that Rig and save the amp volume there to 4.6 as well. That way, if later you'd like to create a new performance that uses that Rig or just the amp again, you can bring it in to that performance and it will already match the reference crunch Rig, and therefore all the other rigs you've balanced to it. The benefit of adjusting the amp volume as opposed to Rig volume (and saving the browse mode version this way) is that should you have a Rig in performance mode where you have dialed in a bunch of effects just so for a particular song, but then decide the amp doesn't suit it well, you can replace the amp in the existing Rig. If your replacement amp was volume balanced already, it will be volume balanced when you plop it into a new Rig.
*Make such volume adjustments in step 3 when playing alone. Do this with every Rig you will use prior to a gig. The way you cut in a mix will vary on the situation, balance for that in the next step.
4) Place a graphic EQ effect in the X slot of the Rigs you perform live with. Since your levels area already balanced when playing alone, develop an ear for which EQ adjustments affect how you cut in the mix as you will have less time to make these changes during a sound check. If particular Rigs aren't as loud as others you probably need a bump up in the high mids. Since these rigs already match when playing alone, use the EQ to fix the ones that seem to disappear in a mix.
5) solo boosts. Most guitarists only have a need for different volumes when soloing. Having an EQ in the X slot is again beneficial. Since it has its own volume control, you can make that adjustment here when you want a solo boost, which also gives you the option to toggle to volume boost. Should you also want to engage an overdrive or boost before the amp section (which tends to just color or increase distortion not perceived volume) you can set it up so one press will toggle both the pre boost and the post volume boost from the EQ.
6) Delete old performance mode Rigs. If you have a bunch of Rigs made of the same profiles, but which weren't organized or volume balanced, why have them? If it's because they contain specially dialed in effects, then consider saving the effects as presets. If there's a combo of effects you want to keep saved as a single unit, then it's worth taking the time to volume balance its profile to the default Crunch. If you hate losing things permanently, save them to the local folder in Rig manager and delete from the KPA itself. Consider re-naming Rigs you have volume matched with a special character at the end so you can stay organized.
7) Limit the number of profiles you use in a gig, regardless of how many performances you create using those profiles with song-specific effects. Your core tone, the profile and overdrives pushing them shouldn't be different for every song. Have a set of profiles that give you the gain stages you need. Maybe have a second set you like better for a different guitar you may use. Maybe even have a couple others that do whatever special thing you need for a specific song. But it's hard for the sound tech, the band and even yourself to constantly have your core tone changing.