Yeah it sucks, I found mopidy-spotify to be janky in it's usage but it was the least worst means of playing audio from various backends. It doesn't look like there's much hope for it in the future https://github.com/mopidy/mopidy-spotify

edit: after looking a little deeper it seems there is indeed quite some activity and hope https://github.com/mopidy/mopidy-spotify/issues/110