??? Why Don't More Streaming Services Do This ???

I feel your pain. I was a big Pandora fan too. If you want the best of both worlds, you would need Roon with one of the better sounding streaming services (Tidal or Qobuz). That’s expensive. Worth it? If you can swing it. 

Yes I will admit the quality of sound from the other services is slightly better,but not enough for me to justify the extra cost on a monthly basis.

Why are you even here?  Go enjoy Spotify and hang out on Reddit.  

Both Tidal and Qobuz have related artists, albums, and tracks you can use to find new music similar to an artist, album or song you like.  Tidal has suggested tracks as part of its play queue features.  Tidal and Qobuz both will play similar music at the end of a play queue (you have to enable it in Qobuz, I believe it’s the default in Tidal).  I am using the macOS versions of both software though so I have no idea how well Tidal Connect works wrt these features.  I’m also not sure how similar this functionality is to what you experience with Pandora.  I have spent hours digging into related artist, tracks, and albums on both services though and let plenty of playlists or queues play through to the point that the service chooses the next track.  I’ve had Pandora and don’t miss it at all, and of course sound quality is much better on Tidal and Qobuz.

I can't understand complaints about ease of access to music in this, the golden age of our access to so much music. Between having  Roon integration with Qobuz and Tidal, and favorite FM radio stations that also stream I easily discover great music every day. And to complain about cost, its practically a crime how little we pay for all this music, does anyone care about the artist! Nope, we are being indulged these days, be mindful of all you have. As for algorithms, I'd rather think for myself, I built my huge library, didn't rely on some stupid robot for vast majority of it.

On Qobuz, use the context menu and select "Go to radio."

On Tidal, use the context menu and select "Go to track radio."