first game = red, blue and yellow came out on 3DS (eshop)
Probably 2D is mostly nostalgia too but the 3D designs are a bit... childish? I don't know, there's something odd in 3D games.. Not full 3D, I mean like Pokemon, Harvest Moon... some games that where 2D and became 3D. I mean, Zelda in 3D is better, so it depends of the game I think.