I was in the same boat as you. I searched for months but there is nothing out there that works consistently.
I ended up paying for a service that let me download my entire Spotify library and then cancelled the subscription. I then cancelled Spotify and now get so my music through Lidarr and play it through Plexamp. I’m really happy with this setup for the most part, however…
Be aware that Lidarr only downloads full albums, not individual songs, so that’s a drawback.
Also, it’s best to have private trackers (usenet AND torrent) to get the best experience out of Lidarr. I had to spend about a month getting invites to several exclusive Torrent and Usenet sites but once I did Lidarr finds most things. I have to get some obscure things by hand still, though, as they aren’t in Lidarr.