My own opinion is that family coasters under a certain size (e.g. Flyingfish, Barnstormer, Hippogriff) get something of a "pass" because they are small enough to be absorbed by trees and landscape without dominating their environment (or nearby environments).
Temple du Peril/Raging Spirits show how a somewhat bigger scale coaster superstructure can be sold as "archeological scaffolding." I think Thom Schillinger put together some cool ideas for Disney Paris on how to theme a bigger scale coaster to a tree-top jungle village
http://3dconceptualdesigner.com/3DCD_2D_environments/ - although that might have been challenging/expensive to pull off if built at a mega-coaster scale.
I think California Screamin loses its 'old woody' look the closer you get to it - I would have liked to have seen wooden (real or fake) timbers overlayed on the steel structure to help sell the area as a unique, turn-of-the-century boardwalk.
Crystal Wings has got to be the most elaborate theme-ing ever done for a mega coaster, I only wish the pylons themselves were themed to integrate with the "ancient citadel" look. It's like you've told 90% of the story, but left off the ending.
Seven Dwarfs Mine Train looks to be brilliantly executed (granted it is of moderate size) to feel like something beyond a roller coaster, joining the tiny number of really convincingly-themed outdoor coasters.
However, if you still want to do it just take a bus to CR and walk to MK or monorail to MK/EPCOT or take a bus to Poly and walk to TTC for all 4 parks or walk over to SSR and take a bus from there. You didn't hear it from me. If you were thinking about bringing an old refillable mug to take advantage of the "free drinks" they put in machines to stop that too.
