Question about boost - for solos primarily. How do y’all like setting that up? I’ve used presets thus far, where one is just louder (either by way of amp gain, volume, or an EQ block). That’s OK, but sometimes I start my solo and it’s too loud, or not loud enough and then I have no options. Thinking I could route the expression pedal to an EQ-based boost maybe so I have some leeway?
I’m sure there are 100 other options so I’d love to hear what your favorites are.
I have the same issue for gigs without a mixing guy or girl.
I have my lead sounds a bit louder than the rhythm sounds and on top I’ve added an expression pedal to adjust volume.
Still not ideal but at least I can make changes on the fly without bowing down to the QC.
I guess generally around 3 db clean boost is common to use for lead tones, regardless the situation. I assigned 2 stomp switches for the lead, one is gain boost but volume doesn’t go up (adds a bit mid, meat and sustain), and the other one is a clean 3 db volume boost. If the tone is suitable I step on clean boost and volume goes up, if I also need more gain I step 2 switches at the same time. Causes a bit tap dance but I like to have options.
If you want to go super adjustable:
Set up a ‘solo’ scene with a gain boost after the amp. Then assign an expression pedal to that boost, but limit the range. E.g. heel down boosts 0.5dB, toe down boosts 3dB.
If you only use the gain boost on that scene, you can still keep the expression pedal for other blocks on different scenes.
Coming from tube amps I usualy subtract instead of add volume after the amp. So I put an EQ after the amp and turn it off. Then I crank the amp to whatever volume I need for solos.
Then I engage the EQ and reduce the volume to whatever rhythm loudness i need at that venue.
A Volume pedal in the Loop pretty much has the same effect.
Pro of the volume pedal: when you engage your solo mode you have some control over the amount. So maybe its a quiet song and you don’t need the whole boost.
Cons of the pedal: more cables on stage (talking about real amps).
In the QC you can adjust the amount parameter via expression pedal. Which is pretty nice
I have an EQ block on the last stomp pedal that adds 3db of volume to the overall level of the preset when it’s time to shine 
I’ve found that the amount of boost needed is dependent on a few variables. If the band is playing louder or in a noisy or acousticaly “live” room, it takes more boost to cut through the mix. I use scenes for some song-specific presets but mostly I I use rhythm and lead presets as I tend to like a fatter tone, with altered effects for solos. I built a small box with a 10K “volume” pot, connected to an expression jack, that controls a gain block in solo scenes and presets. This allows me to control the amount of lead boost globally, without altering the level of my rhythm tones. I also have an expression pedal that controls my global volume (regardless of preset or scene). This gives me enough control to adjust to any situation, on the fly. This works well for me, anyway. 
Same issue here. Sometimes my lead cuts through, sometimes it doesn’t. So, I’ve assigned two scenes for lead. One where it’s a normal boost and one where the boost is even louder. Depending on the room, I’ll use one or the other. I always start with the normal lead. I’ve never used Boost, just amp output control or a gain block or the volume level on a drive pedal.