That'd be fine. It doesn't need to be truly outdoors - just have some degree of sunbathing light. I'd most want it to have trees and stuff, though (albeit perhaps maintained in kind of an over-the-top way, since this is the Gold Saucer we're talking about).
I've actually been humming that stupid in-show commercial from King of the Hill to myself - the one where it's like "get wet, get wild, get cool, go bana~nassssss!" We have a small local water park here in the Pacific Northwest that almost has the same theme verbatim :P.
