"We Are the Champions" is the missing song that's puzzling.
"We Will Rock You / We are the Champions" is in Lego Rock Band
, which features exporting into RB2. I'm guessing that's the reason for its absence from the pack.
As for "Bohemian Rhapsody," I'll bet anything that Harmonix is holding onto that one until Rock Band 3
is released, utilizing the vocal harmony technology developed for The Beatles
If Harmonix doesn't want band members to get bored during a song, then why did they pick "Cool for Cats" and "E-Pro?"
Well, in the case of "Green Grass & High Tides," the singer's role when the first solo starts is to shotgun a six-pack of beer and knock over as many pieces of furniture as possible in the allotted time. It's a minigame, you see.