Gah. Gamers are often too stubborn. They complain when Mario's story isn't more than "Go rescue the Princess and shut up" and complain when Metroid's story is all elaborate and such.
One thing you all must understand is that you can't wish for Metroid to not have a story: It already has one. Not the most original one at first glance, but full of details and beautiful when seen with more depht.
And why does, suddenly, more story automatically relate to lack of gameplay? Even if you say an established story means forced linearity, there are games (Metroid games include in this, though not so deeply... yet) that have multiple endings depending on how you play the game, with one being the real ending that leads to sequels and others being alternate endings that relate to your progress through the game.
Finally, I don't see how cutscenes can create a bad game. Metal Gear Solid 4 and Uncharted 2 are full of them (quite more than what I've ever seen in a Nintendo game) and they both got many Game of the Year awards...