My dear man,
You may not realize the full brilliance of your concept. (The vast majority of the brilliance is realized, no doubt, but allow me to elucidate.)
I loathe guitar hero/rock band. I think them to be perversions of a truly beautiful art. Their gameplay is, fundamentally, pushing buttons when a flashy light tells you to. I am yet to seen a better example of operant condition since the skinner box. At least the rats freed themselves for food, we are doing this for... game grades? Points?
HOWEVER, despite my distaste of that game structure, I think your idea to be a stroke of genius. It ceases to be a whimsical fantasy, attempting to emulate people who have more money than God, and it becomes a game, with a controller, and a *gasp* plot.
In any case, delighted.
Cheers