The biggest gameplay issue I had/have with Rock Band is the lack of notification about how the players earn points.
On the mic, activating overdrive can be a simple blow in the microphone. AND during BREs, you simply yell ONCE to activate it. ONCE. That's it. Sound waves are nice, but don't KILL yourself. It does NOTHING.
On the guitar, the whammy does NOTHING in terms of score. Nothing. During overdrive notes, whammy (AT ANY PACE) will slowly increase overdrive, but fucking with it is the same as a smooth back-and-forth motion.
On drums, yeah, drum fills are 0 points. Once the crash gem is popped, that's it. Hit it. There's no need to go nuts.
They realllllly need to hammer these points home in RB2.