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.)
Outer Wilds. I consider it the best video game ever made and I’ve spent quite some time thinking about if there’s something I could add, change or remove that would improve it and so far I’ve yet to come up with anything of substance (beyond tiny QoL changes or reeeally nitpicky stuff).
You could always add the DLC :D (I’m half joking of course, but it’s soooo good. I think it’s on par, if not a little bit better, than the main game.)