I believe The Beatles: Rock Band came the closest to being perfect. Eveything about that game was just beautifully done and the only things missing was Pro Drums, an option for Keys, and a few more Beatle songs (Hey Jude, Strawberry Fields Forever, Yesterday etc. etc.)
It’s Ocarina of Time for me. It’s just about as perfect as it can get.
It blends the simplicity of a platformer with the complexity of an open world RPG with just the right amount of each.