We use bandhelper and love it!
Is there a way to have notes related to a song that are user based? Like the singer wants to have the first line, but others want other things (like Drop D, or effects pedals, etc).
The simplest way is for users who want personal notes to turn on Settings > Account Sync > Personal Sync > Notes. Then a Personal Notes field will appear for them on the song edit page.
If you want more structure or want to share a note among multiple users, you can go to Repertoire > Custom Fields and add custom fields and assign them to any combination of users.