I would most like to see a new pikmin game on the DS, I think it would make good use of the touch screen controls.

I'm a big fan of paper mario too, but there is already mario & luigi partners in time which is pretty much the same thing.

As much as I like the Smash Bros. games, they would not work well on the DS for one simple reason: you can't perform smash attacks with the D-pad. And that is pretty much what the entire game is based around. I mean, it's even in the title, and we can't have plain old Super Bros DS. Also, since the screen is so small it would be impossible to see anything when the view zoomed out.

But if nintendo did make smash bros DS i'm sure they would find a way to make it as fun as possible.