[Guitar Woman]

No More Heroes and Mario Strikers Charged are the only things you should pay cash money for.

Madworld is coming out soon, that'll probably be sweet!

I sort of like Super Paper Mario.
If you don't have it on another system Guilty Gear Accent Core is probably worth looking into.

Megaman 9 is fantastic and Art Style Orbient is pretty interesting, but I haven't played any other downloadables that aren't Virtual Console titles.

You probably wouldn't go wrong with a little Homebrew action, either.