Sonos has been saying for several years that they’re going to add services to their API, but that has not happened. So every integration out there is hobbled in that area. The issue of Spotify is even greater as they allow no scenario when you can do anything but use their app, that’s just a Spotify thing. Even HEOS and SoundTouch, which both provide more integration than Sonos, do not provide anything for Spotify other than exit to the Spotify app.
The .TRANSPORT SET and such commands do still work in ways that no other product I’m aware of enables.
If by stations, you mean Radio, that works fine. If you mean Sirius XM, that’s different. Normal Sonos Internet radio works fine. The Music Library also works great. It is up to Sonos to allow services at this point. Indications are still positive FWIW. While this is the goal, it’s also important to remember we are on iOS not some custom control platform. The Spotify app is one swipe away and can be multitasked right alongside Roomie.