for me it's really heavily split between Touhou and Sonic.
Touhou has The Gensokyo the Gods Loved, Romantic Fall, Candid Friend, Because Princess Inada is Scolding Me (
honestly i love the whole of MoF's soundtrack), and probably also unironically Bad Apple!! (PC-98 Lotus Land Story) and if i get around to it, i'll listen to all the other games' soundtracks too.
but Sonic has Chemical Plant Zone (STH2), Doomsday Zone, Lava Reef Zone, Hydrocity Zone, Sky Sanctuary Zone, and Ice Cap Zone (STH3&K), Sonic Boom (Sonic CD), Can You Feel the Sunshine (Sonic R), Speed Highway, Chao Garden, Open Your Heart, Live & Learn, and several others (Sonic Adventure 1/DX and 2/Battle), and the whole soundtrack for Sonic Rush slaps as well
ugh, Sonic soundtracks in general are bangers. i dunno, i guess i just love chiptune, mostly synthy like Mega Drive (Genesis for the rest of the world) and PC? Sonic and Touhou crush it with chiptune (more synthy than 'blip bloop' like NES or Game Boy)
though, Hideki Naganuma makes great soundtracks too - he made the Sonic Rush soundtrack, but he also made most of the Jet Set Radio soundtrack! (my fav tracks from Jet Set Radio/Jet Set Radio Future are Let Mom Sleep, Funky Radio, Humming the Bassline, and Rock It On)
also i loved LittleBigPlanet's soundtrack, mostly because it's so calming. mostly the original soundtracks though, like The Gardens and The Metropolis especially...
also Persona has such a good soundtrack too. and i loved TWEWY (The World Ends with You) as well.
and a bit out of my comfort zone, but the Hoyoverse games in general have a great soundtrack too. Genshin's soundtrack is really calming for me, while Zenless Zone Zero's lofi when in the open world is some of the best for me!
there's so much, it's kinda like my music taste is sharply half-and-half with Vocaloid/UTAU and video game music lmao