This is a very difficult list to compile properly. I haven't ever heard of anyone with an exhaustive list of all releases to compare them properly. It's pointless just comparing the Hollywood 91, EMI 94 and Japan 01/04 as all these releases are fairly rubbish. The Japanese sound good at first, but the more you listen the more you realise Pete Mew has EQ'd the hell out of them.
Further, you need pristine copies of first press vinyl to use as a half decent reference points. Collecting decent early press vinyl is very difficult in itself. Some sound ordinary, and the odd one sounds fantastic. Overall, good quality vinyl beats even the best CD's as the naturalness of instrumentation and dynamic range murders digital. Of the remastered vinyl I've heard, A Day at the Races Millennium Edition sounds magnificent. A Night at the Opera centenary edition is nice, better than the half speed mastered 30th anniversary to my ears (although virtually all of these were warped). Unfortunately I haven't heard the DCC ANATO or the MFSL versions of The Game, ADATR or ANATO.
As for CD, there is far more crap then decent releases. To do a proper comparo you'd need someone with the full suite of first release CD's along with the DCC ANATO and the MFSL NOTW, ANATO, ADATR and The Game. I have the ANATO Bob Ludwig 2005 release which is very good, but I don't have the DCC/MFSL to compare with (but my vinyl is far preferable). Add to all this, The Game, News of the World and Greatest Hits Target CD's from West Germany which receive very favourable reviews and you start to see why a proper comparison of the quality versions is very difficult!!!
I have the MFSL News of the World which is the best digital version of this album that I've heard. The Game from MFSL is also the best version I've heard, but not as involving as the News of the World release. Possibly this was down to the original production or maybe I just can't get past that lovely 70's sound!
One day I hope to have the complete list but I'm several years and lots of dollars away. I think it's too much to expect Universal to do a proper job and make the various back copies redundant, but I can keep hoping.