Lol @ some of the advice in this thread.
I've been a FOH engineer for over 15 years now. Guitar tone in any given venue is a moving target. There is no one-size-fits-all solution. This is why there is a guy out front whose job it is to fiddle with his knobs(!) to make your sound work within the constraints of the equipment and room that it's creating sound in/through.
That said, I would say it's fairly simple from your point of view: get a good studio sound going on your KPA's main outputs. Your FOH engineer will be pleasantly surprised by that. He will do whatever needs to be done to it (maybe a HPF, maybe tame some high mids) to translate it to a PA. Assuming that he knows what he's doing (most pub engineers don't) and that the PA doesn't sound like a sack of ass (most small PAs do). Although if you're rolling with a studio-processed profile (e.g. you profiled the complete studio signal chain of your last record while you recorded it), theoretically he should be able to leave it flat if the PA is tuned well enough (hah! Too many hack system techs in this business...)
If you're unlucky with the FOH engineer and the PA, NOTHING you can do with your Kemper will solve that. Employ a FOH engineer to gig with you, and buy a decent digital mixing desk for him to use (even an X32 if you have little cash). If you can't afford one, you're just going to have to deal with it and make the best of a bad situation.
If your doing a gig at a large festival, or supporting a large tour (I'm talking arena size gigs here), generally speaking they will have high end PA systems and decent system techs and decent FOH engineers to run it all, and in that scenario you have nothing to worry about with your nicely studio processed profile.
All you gotta worry about is using your monitor EQ to adjust the tone coming through your cab (this is why we're all asking for parametric EQ on the monitor out) on stage to your liking. Don't sacrifice the FOH sound just for your monitoring. Remember: you are one person on a stage. There may be hundreds or thousands of people out there expecting a nice sound from you. Why ruin their experience just for your ego trip of having a nice sound on stage?
Oh, and protect your Kemper. Shock mount it - don't use one of those cheap racks with no shock absorption. Get a proper one with rubber or foam between the rack strip and the outer case. Or build your own if you have workshop skills.
And carry spares of everything (even your KPA) if you can afford it. When the SHTF you'll thank me.