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.)
Knights of the Old Republic - I know KOTOR 2 is probably better storywise, but there’s bugs and cut content (even with TSLRCM) which drag it down. The first game is a solid banger, I still remember my first playthrough when it came out (installing it over 4 discs!) and the revelation near the end of the game blew me away. I still replay this yearly.
Mass Effect - Fuck me, what a game. I know everybody rates the second game the most, but for me the first one is absolutely perfect. The air of mystery, the size of the galaxy and the overall atmosphere are second to none. I never had an issue with the combat (just don’t use the cover system and it’s literally fine) but that’s sorted in the Remaster. Again, replayed annually.
Dragon Age: Origins - I mean where do we start? Refines the mechanics from KOTOR and introduces an incredible, original dark fantasy world. So much replayability because of all the different origins and choices you can make. The world feels fucking hopeless and every choice you make is seemingly about harm reduction rather than ultimately “good”. I try and replay this annually but I’m currently trying to work through DA2 and DA:I (the quality of these games really shows how good DA:O is).
I’m aware that I’ve only chosen BioWare games from a certain era, but I just absolutely love them.
Dragon Age was a bit much for me. Quite enjoyed the gameplay, but I was overcome by the impressive but very prolix lore.