To be perfectly honest I'm not a big fan of their output after Reckoning and before Out Of Time in general. I seem to remember Document being my favourite from that period but that stuff all tends to blur into a big beige mulch for me.
Here's a mini theory of mine: much of REM's discography can be viewed as duos that are two sides of the same coin:
Murmer/Reckoning: the sprightly early style, not massively dissimilar.
Not sure how well it works for the next four.
Out Of Time/Automatic: upbeat mainstream pop / melancholic mainstream pop
Monster / New Adventures: overproduced rock / underproduced rock
Up/Reveal: muted melancholic dreampop / happier colourful dreampop
Around The Sun breaks the pattern.
Accelerate / Collapse: 80's REM throwback / 90's REM throwback