Sing to god is not my favourite. pared down to 45 minutes of my fav bits it could be perhaps, each disc has a handful of all time cardiacs classics, but there are also a lot of tracks that slip right through me. The weaker tracks are still cool in a “how the hell does someone come up with this kind of stuff” sort of way though.
Heaven Born and Ever Bright is my least fav of theirs, its just really hard to digest the tunes on that one. I actually enjoy Guns and LSD more than either of those, which might be a minority opinion idk.
Not sure if you’re covering live stuff but All That Glitters Is a Mares Nest is a killer live record, this band pulling off these songs live is quite something and their zany stage show is a great time (see it with the video if you can, it’s on youtube!)
I havent listened to them enough to digest them properly but two volume “Special Garage Concerts” is a pretty neat performance of the band’s early material rerecorded live in high quality so that you never have to bother listening to their early cassette albums like The Obvious Identity and Toy World (which are great musically but unlistenably bad in terms of audio quality).

I think I’d rank their albums:
On Land and in the Sea > Whole World Window > Songs For Ships and Irons> LSD > Guns > Sing To God > Heaven Born

thriller just isnt that interesting as an album. a collection of some of the greatest singles of all time sure. but a proper “album” as it were? nah.