BTW, "Gravity" is 40 BPM, if that matters as far as "slowness" goes.Yes, agreed on 3/4 and 6/8. Note that many of the songs mentioned on this old thread are in those time signatures. The Eagles "Take It To The Limit" has both.
My band plays John Mayer's "Gravity," which is a slogging 6/8 with a tricky bass drum part. And what else would you expect from Steve Jordan (studio) and J. J. Johnson (my favorite live version).