I can't give an opinion with Metroid since I haven't played either the 2D games or 3D games.
But out of Mario and Zelda, in terms of still feeling like the games before it, Zelda wins. Except with Ocarina of Time, for me I never want to explore much, but I feel obligated to do it with something like A Link To The Past and obviously the original Zelda.
Can't wait for The Zelder Scrolls 3: Breath of The Wild Hunt!







