Filter liked songs by "Not in any playlist"

[BdubsNYC]

I have thousands of liked songs but I really only listen to songs in my own playlists. 50% of my liked songs have been added to my playlists, the other 50% haven't. There is currently no easy way to figure out which songs have not been added to a playlist.  I end up not listening to half the songs I've liked.

Would love to be able to sort my Liked Songs by "Not in any Playlist" so I can easily find the songs I liked at one time but got buried in the dumping ground that is my Liked Songs. 

[Marion15]

Good Idea I have no Idea how many of my liked songs are never used again. I have created some general category lists for new/liked songs . And try to add new ones to LIKED + A category at the time of discovery. Hoping they won't be lost forever. Some are in several mixes. That would br useful info too. Some mixes evolve to sound the same, I liked them over and over then get tired of both.