I think it's wrong to attach these art styles to some of them people...
Sakaguchi, Miyamoto and Kojima aren't visual design artists after all.
Take Blue Dragon... a Sakaguchi game, with designs by Akira Toriyama.
Take Wind Waker and Twilight Princess. 2 Zelda games using 2 completely different styles. But made by the same people, same producer.
You mention Sakaguchi and Amano as being sort of the same, yet Sakaguchi was not responsible for the looks of the Final Fantasy games he produced. Amano (and Nomura) were responsible for that...
Either my own artistic background is preventing me from seeing what you're trying to convey, or there is something inherently flawed about your thread.
EDIT: Also, the 2 pictures you have for Amano's work aren't even his work to begin with.
