If you look at Banjo Kazooie and Sunshine (in the main stages) you'll notice one peculiar thing: an almost complete lack of traditional platforming obstacles.
Rotating platforms. Spinning blocks. Sinking stands. Ground that slips away and falls beneath your fit. From what I remember of Banjo, it has almost none of this. Sunshine has a bit more, but it's few and far between, and it rarely places a series of them deliberately between you and your objective.
The (top part) of the Pianta village level is pure Banjo. A flat, square grid with a bunch of hills placed haphazardly around the map. No platforming obstacles . Certainly nothing resembling a path you have to take. Gelato beach is the same thing. It's as if Rare and then EAD decided to make a bunch of hub levels as the main levels.
Mario 64 on the other hand is an extremely clever little bastard. Many of the levels are spirals with strong vertical elements. A hilltop. A fortress. A snowy mountain. A tall tall mountain. A clock. It takes a star, and it puts it at the top, or sometimes at the bottom of the level. You've got to work to get it. You have to pass the traditional obstacles the designers purposefully put in front of you on an obvious path. Off the beaten path are opportunities for exploration and hence your other stars.
But, that's only half the story. The tight spiraling structure of a Whomp's Fortress or Tick Tock Clock means endless opportunities for creative platforming. And Mario's mechanics allow you to take full advantage of them.
Mario 64 never forgot it was a platformer. Maneuvering up and down Whomp's Fortress, with its vertical structure and obstacles and enemies which are all trying to kill you, is a lot more interesting to me than meandering around Gelato Beach with its static trees and static beach houses and static mountain path. I still think Mario 64 is the only game to get open 3D platforming stage design correct.
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