Sonic. Every game in the series has great music, even '06. The single exception is Chronicles, which is actually known for its music for being the single entry that doesn't have good music. The "Classic" games of course have classic music, the cheesy pop rock from the Adventure era is a bit cringy but an undeniable guilty pleasure, and while I don't like the washed up 2000s pop bands they've gotten for Modern Sonic's music as much as Crush 40, they're still good.
But a lot of the best songs aren't the ones people immediately think of. Obviously Sonic CD has great music, both the American and Japanese soundtracks. The Japanese soundtrack is better because it's more cohesive, but the individual tracks from the American one are still great. The Master System/Game Gear games still have great music. In fact, the Japanese Sonic CD theme is originally from Sonic 2 on Game Gear. Sonic 1 on Game Gear also has a song (Bridge Zone) that was good enough to later be remade as Tails' theme from Sonic Adventure.
From the Adventure era, people remember the main themes, maybe the character themes and a few meme level themes like Pumpkin Hill, but Metal Harbor is maybe my favorite from its game, just with its awesome guitar. Heroes I would say has a horrible main theme, a huge step down from Open Your Heart and Live and Learn, but the character/team themes are great, especially the ultimate guilty pleasure, Team Rose's theme. Extra shout out goes to Metal Sonic's theme, which is right up there with Open Your Heart and Live and Learn, but you only hear it during half a boss battle, so most people probably don't even notice it.
Another thing I like in Adventure 2 specifically is that they did new versions of the character themes from the previous game. Tails' and Knuckles' themes were not as good as the versions from Adventure 1, but it was still neat to hear the new versions. Sonic's "It Doesn't Matter," however, is awesome in both versions. Either way, I love that the songs are from the perspective of the characters, and trying to use musical styles that make sense for them. They all give strong insight into the personalities and motivations of the characters. They add a lot to the story.
Again, even Sonic '06 is full of great music. I distinctly remember being super excited for that game for about a year before release. The PS3 version was delayed, so I avoided spoilers for a bit while waiting for that version to come out. Also meant I missed people shitting on it. But I get the game, beat it in a week or whatever, and distinctly remember thinking, as the credits rolled, "well, the music is pretty good I guess." A sad consolation for an otherwise disappointing experience.
Modern Sonic's music, to go with its different, lighter tone than the rest of the series, also has lighter music aimed at a slightly younger audience. As such, it's slightly cringier, but hey, all the songs with lyrics have been cringy. But that's okay. It fits the tone of the games. I understand they're aimed at 12 year olds. They do a good job with that.