Getting the PA set up right and balanced nicely can have a surprisingly large impact on the atmosphere in a church and the congregation.
When the worship group are confident in the sound, and can hear everything they need clearly in their monitors, it really opens the way up to being able to lead worship freely without their attention being drawn to the technical aspects.
But before you can get stuck in to setting levels and EQ’ing, the first thing to get right is your gain structure. It might sound a bit over-geeky but when it’s right, it will make your mixing much easier and will reduce the chance of feedback. You’ve probably already been doing this without even noticing, but being really aware of it and anticipating the next stage in the the gain structure will improve your next live mix.