I was re-reading the ogre section in Classic Monsters Revisited.The description of the ogres' late night jamborees, gave me an idea. Some theme music to help set the stage for players encountering one of their shindigs.Not necessarily the music the ogres themselves are playing, but something to set the mood.Something to capture the essence of hulking sadistic degenerates but with something of a hillbilly sound as well.
If the GM ever wants to raise the effective CR of ogres without actually changing them there's a very easy way to do so. Just equip your ogres with longspears, simple weapons with which they are already proficient, and BAM they are suddenly much more combat-capable. I've done this. Players were initially shocked but swiftly came to terms with the new ogres-can-actually-be-dangerous reality.