Actually... I will respectfully disagree with you on theming. When you talk about the attraction being underthemed... what are you basing it on? Are you basing it on the number of times the Carnosaurus appears in 'Dinosaur?' How about the ratio of scenes or AA's seen per minute when you go through a typical Disney ride?
After seeing the backround videos that Joe Rhode and his team did while researching this project overseas... I think he and the rest of imagineering stayed true to the legend and themed it very well. It was believe that there was only one, yeti creature. The creature was mysterious and seen rarely... but only in glympses. If you saw it... it was attacking. The inhabitants around its home had shrines to it. they lived simple lives, they had prayer flags, and they had reverence for the creature. The trip is not going to have AA scenes where locals are venturing to or up the mountain... because they just didn't do that. And as the ride concludes... you only get a brief look at the yeti.... narrowly escaping certain doom.
So I disagree about there being a lack of theming, based on the backround journeys of the imagineering team.
You make good points, but this reminds me of something I remember hearing Walt Disney say once, "I would rather entertain and hope that people learn something, than educate and hope they are entertained." Walt was a smart guy who clearly knew that his place in the world was to entertain people. We can probably all cite examples of his films, theme park attractions, etc that occasionally deviated from historical, cultural or scientific accuracy in order to maintain a high degree of entertainment value, while at the same time not "talking down" to his audiences. Not many people have been as successful at carrying on that practice, and having the instinct to know when to tip the balance somewhat so that people come away being wowed! But if we are to look to anyone to continue that value, I would think it would be his Imagineers. In the case of Everest, I can understand and respect the desire to want to make the attraction as true to the culture and traditions as possible, but not at the risk of building an attraction that is lacking in themeing and adventure. I would hazard a guess that many people expect adventure when they embark on an attraction about Mount Everest and the Yeti. I don't know that many people really come away from this ride saying, "Wow, I really feel I learned a lot about Himalayan culture and have more respect for it now."
So I think that you've actually provided some insight (although perhaps unintentionally) into why this attraction really lacks the level of excitement and adventure that Disney fans like me look for in a Disney attraction.