Having buttons on the presenter screen that the operator can click to play royalty-free instrument-only music that fits a specific vibe. For example, the buttons might be "Hosting," "Game," "Reflective," etc...

Here's a folder of music we made for this type of thing at a church I worked at a while back. Each mp3 is over 20 minutes long, so we didn't have to worry about it fading out at weird times: