I like a mix, but then I'm the kinda guy who loves expanded worlds and ridiculous in-depth(but hopefully optional) exploration of a series. The dictionary in Mass Effect is a great example.
Like in Metroid Prime 2 where the marines are there, but just to get crushed by rocks and shit in the intro before it becomes a Metroid game. But you can still scan things to your heart's content, so I was happy enough(as happy as a fella can be playing Metroid Prime 2, ffffuck you mcguffin sequence.) But you know it still kinda sucks that the marines literally exist just to be crushed by a rock as scenery.
I didn't really care either way with a narration like Fusion or a re-imagining like Zero Mission.
And I've barely played 3, which as I recall was knee-deep in extreme characterization(thankfully, just of everything in the Galaxy BUT Samus) before you even finished the intro.
I dunno it wouldn't hurt to give it a try and Team Ninja seems to know how to make fun games, sex-doll jokes aside.
EDIT: Rereading that I guess I don't mind if they go Fusion on us and give us a story with some words, but hopefully it can be a fan-obsess-your-own-adventure deal like Prime's scanners were.