For the songs recomended to playlists i have i have noticed they will usually be grouped around albums in said playlist that are made by multiple artists. IT seems to me that somewhere along the way the algorythem is searching for playlists with similar artists for recomendations. I would say this could bve improved if the relation was also in some way inverseley effected by the album as well as artist so as to refine the search to more similar playlists rather than just ones with those said albums on.
Hope this makes sense as think it will help.
Updated on 2019-09-12
Do you mean you'd like to have full albums recommended instead of separate songs.
Looking forward to your reply.