I feel like so many people will have different answers, and a lot of it will have to do with which era one started playing. I would say that gameplay-wise, <em>Heart Gold/Soul Silver </em>probably claims the number one spot due to the fact that you can travel to multiple regions. However, <em>Let's Go Pikachu & Eevee </em>has the gameplay advantage of couch co-op, which is a ton of fun. Aesthetically, Gen 3 is my favorite, with <em>Emerald </em>likely being my favorite overall game.
