For me, since I use only a processor (Helix) and don't use any amplifiers on stage, it's super simple. My guitar is mixed in just like everything else. We recently hired a sound/light tech who takes care of the mix during the gig. Since none of us use physical amplifiers, it makes for a cleaner sound since you don't have this din of stage noise bleeding into mics and generally making it near impossible to hear what's going on.
The burden is really on me when I build my patches to be sure they have a pretty consistent output level, but it's not that hard. I also usually build in a "Lead" snapshot for most patches to boost my level (and adjust any other effects, if necessary) for doing solos and such.
Ideally, we do two sound checks. The first sound check is just to get our in-ears set right. Since we all have an app on our phones/tablets that allows us to control our own monitor mix, that's pretty simple. The second sound check will be full PA which gives our sound tech the opportunity to set the PA levels.