I ultra so heavily disagree on your disagreement . KEA is a fantastic album, with a lot of NWOBHM inluence filled with great songs like 'Motorbreath' , 'Whiplash', 'Seek And Destroy', and more. AJFA was the last decent Metallica album, and if it wasn't for 'One' and a couple more fillers it would have been a better one. But it is not boring or utter crap. You forgot "The Human Factor". But even if I love Howe's era Metal Church I won't go and compare to classic Metallica. Both are great on their own. To say one is better than the other is always subjective to the listener. I don't know why people bash Metallica for that (I do for a 100 other reasons). Hetfield vocals were distinctive of the band and much more enjoyable that say Kreator or Sepultura at the time. Surely better than Mustaine if the eternal comparison between those bands may arose. The thrash voice concept you are try to point escape my comprehension. From Ron Royce to James Hetfield, Dave Mustaine to Chuck Billy, Chris Astley to Mille Petrozza, David White to Joey Belladonna, Jimmy Hamilton to Bobby Ellsworth, there are a lot of ranges, pitches and singing styles. Thrash to me can be defined by rhythm, melody, guitar solos, speed, ferocity, technicality but not for vocals.