List of optional mods:
Better Florans
Better Tails for Kitsune
Dark Souls Broadsword Idle
Dramatic Deaths
Enhanced Chat Readability
Extended Songbook
Frackin Interface
Frackin Music
Make the Arachne Cuter
Make the Lamia Cuter
Make the Lamia Into a Tatzelwurm
Make the Saturnians Cuter
Make the Universe Cuter
Metal Gear Solid Alert Sound
Outpost Music Replacer
Taehl's Teleport Beams
What Menu?

All mods that add music into the songbook are also optional. Feel free to add other optional mods to your own client.