Have you bothered with The World Ends With You? The only thing I do not see you doing on your ride is yelling to activate a certain pin-type's attack, but it is a crazy-weird story and design to it that makes The World Ends With You worthwhile. Armor? You mean sweet, fashionable threads. Weapons? You mean these super kawaii pins you can put on your backpack. Fast-paced combat takes place on both screens, your support characters are all very different, and seeking out noise can be fun.

How do you feel about the Contra series? Contra 4 is available on the DS and by all reports does the brand justice. I am led to believe that means it is hard, requires you to learn a few enemies' attack patterns the hard way, keep firing like there is no tomorrow, and loads of fun.

Lock’s Quest is a tower defense game made by the same guys who did Drawn to Life and Scribblenauts, and I enjoy all three games. The latter two because I like being creative (seriously, Drawn to Life is a lame platformer, but lets you draw and color your character, weapons, vehicles, and more) while Lock's Quest has actual good gameplay and design. It is fun and frantic.

Hotel Dusk: Room 215. Jessweeee♪ loves it. I am playing it, but I do not know how to recommend it. You click on lots of things and pursue a story?

Also seconding Etrian Odyssey. Get one, get all; whichever. They are all old-school dungeon-crawling fun.