I pan all of my tracks, bass hard left/drums center/guitar hard right. When I add strings, organ or solo instruments they are also center. I do it this way because when I use the Passport I have the stereo option. It doesen’t seem to matter when using mono sound reinforcement.
I will also add that I use the application “Boom 2” on iPad, computer and iPhone. It is an EQ program/app that allows you to store a custom EQ for each PA system or amp that you use.
I have 3 different amps or PA systems available to use on gigs and each has it’s set EQ in the Boom program.