The concept is interesting, thanks for sharing. I suggest that in future iterations/versions, it could take the duration of the tracks into account: a two-minute track certainly doesn't cost as much as a track that is almost three hours long (extreme example, I know, but album-length tracks are not that uncommon).[1]
[1]: https://open.spotify.com/track/6jfQOSSQImYlyxeSAi6jh7?si=375...