the only problem is that for any game to be an actual enjoyable 'game' there has to be some sort of challenge or obstacle that can be overcome by the player(s), which is what creates the sensation of winning / the illusion of progression depending on the style of game.

how do you establish that for a rock rpg without basically lifting the tour mode from the rockband videogames?

what challenges do you throw to the player to make it an actual game as opposed to just playing pretend rockband minus the actual game of playing the songs?