No, they are not overrated. The games you're talking about are now quite old. At the time they were top of their genres.
I don't think Treasure is overhyped, most people just cant get on with their style of gameplay. It often rather deep and you have to gain skills to be good at it. For some games, its enough to have skills you gained somewhere else (i.e. to beat DDP). This wouldnt work with Radiant SG or Ikaruga. Treasure invents new ways of gameplay for almost each of their original games (rsg, silhouette mirage, ikaruga, bangai oh, yuke yuke troublemakers). To be honest, I'm not capable as well to beat stuff like RSG. But I love it anyway, for its style... I never saw that in another shooter (in this way). Its like a scifi movie, meanwhile Ikaruga means truly art to me, not just in the way a game is art but in the way that you could put Ikaruga in a museum for modern gaming arts or i dont know what^^ And as GP said, Ikaruga is the absolute opposite of being basic. Its one of the deepest shmups ever, if not the deepest regarding the fact thats its extremely easy to learn how to score at the same time (unlike RSG or Garegga for example).
