There is something about your idea that reminds me of a demo I played some years ago on X360. You had to fortify a house and build traps. At the same time you were supposed to look for a guitar, and amplifier and a speaker so that you could rock to make the 50's zombies dance and explode. That would win the level for you. Can't remember the name of the game for the life of me though... googlegooglegoogle ... Dead Block! http://deadblock.com/videos
The idea you have is somewhat different which is good <img src="{SMILIES_PATH}/icon_e_smile.gif" alt=":)" title="Smile"> Maybe some fine tuning with character roles would make your concept a bit more unique. Maybe connecting micro-games to character action. For example, let's say that instead of a guitarist we have a guy with a flute (like in the story from Brothers Grimm if I remember right?). You must hit a series of keys/buttons in a rhythm to get the best performance. Just an idea <img src="{SMILIES_PATH}/icon_e_smile.gif" alt=":)" title="Smile">