Why make this more complicated then it is
It is called a "play list", the definition tells you exactly what it is used for...
You make a list of songs you intend to play and the order to play them
It is not your "complete " library. As your "Song book" section on a Korg.
If you are doing an hour show.. the list will be 20-25 entries in the playlist. A 4 hour gig will have 60 entries in the playlists.
It will work the same in your bedroom, or out on a job
Every Play list I ever used or tried... it points to a song and content from your library in memory..