Currently if there is no document or lyrics attached to a song, the document viewer will just display the title of the song as a placeholder.
I think it would be nice if the user could customize this text to show more song meta data (or nothing at all). For example, the user could check off which meta data fields would be displayed (title, artist, key, etc..) and all that info would be displayed if there is no document or lyrics attached.
I understand that you can put all this information into the layout itself but I think this would be a simpler approach for a lot of users.
Additionally, the user could choose to have this information appear as a header in the lyrics field. This would show more information in the document viewer without having to fumble with spacing the fields in the layout editor. The fields in the layout editor also have less options with text formatting, where as a header could be formatted with the lyrics.
This would also address an issue I've come across where some users would just prefer to see the placeholder instead of lyrics.
For example, if I put lyrics on a song for the lead singers, the other band members get thrown off sometimes because they're used to just seeing the title of the song song in the document viewer in our Split View layout. They'd rather just see the place holder. I can use the personal lyrics or hide the lyrics for certain users but that has its trade offs.