GT4 is better than GT3 imo, but if you have to spend money on it, it might not be worth.
I’m mostly into RPGs, and it doesn’t seem like you are from this list. If you are, then FF10 and 12 are available. So are KH1 and 2, and also Wild Arms 3, Personas 3 and 4, Disgaea, Shadow Hearts, Okage, Okami, Star Ocean, Dragon Quest, Devil May Cry, God of War, and so on.
Viewtiful Joe 1 and 2 are silly and fun side scrolling beat 'em ups. Tony Hawk needs no introduction. Silent Hill 2 and 3 if you’re into horror. Resident Evil 4 if you’re into action horror.
Shadow of the Colossus is great if you’re into a quiet, contemplative adventure game.