wayoutwest, I'm not sure I would call 10CC's "I'm Not in Love" an upbeat song (even though the lyrics are downbeat). In fact, it's one of the most downbeat songs of all time.
Think you are right different songs and composers scores can have quite different effects at different times throughout ones life that 10cc track used to make me laugh years ago,but not really anymore,guess its one when you first remember ever hearing it you expect it to be a pure love song,have not listened to it in years.
Here is another one for you that is just downbeat
Always liked this Group and went to the Concert when they where touring promoting this Album.
Check out the lyrics to the original German "Ballad of Mack the Knife." Jaunty melody, lurid lyrics.
Or "Denn Wie Mann Sich Bettet So Liegt Mann" from their opera, "Aufsteig und Fall der Stadt Mahagonny," sung to a tune that sounds like a hymn: "Denn wie mann sigt bettet so liegt Mann, Es deckt einen da keiner zu, Und wenn einer tritt, dann bin Ich es, Und wird einer getreten dann bist du's...
"Then as you make your bed so will you lie, There's no one to cover you there. And when anyone kicks, then it's me, And if anyone gets kicked, then it's you."