So, this idea maybe not possible at the moment. But it will be in the future and maybe plexamp can be at the front here. The people over at musicbrainz have recently (kinda) opened up a new site called ListenBrainz which aims to be an alternative to last.fm and offers it’s data to the public.
One thing that makes roon, spotify etc. as good as it is, in my opinion, is their ability to source recommendations via the listening history of their users. Listenbrainz could provide that kind of data for usage within plexamp and that could enable better recommendations.
So my feature suggestion is for plexamp to get in touch with ListenBrainz and talk about how plexamp could use their data/recommendations.