I've always thought that a real Museum of Antiquities setting with the overlaid theme of a "new exhibit straight out of Egypt" would be really cool. The tombs and artifacts would be coming to life as you sneak into the area from the main lobby. The problem with how it is now is that it's a purported film set "coming alive", so the reality of its artifacts is just feigned.
The exterior facade would be extended vertically to hide the show building first of all. The actual entrance would then be a set of architectural elements from the outside of the tomb recovered from Egypt, and the lockers area would be a heavily-advertised (in the style of 1950s NYC) outdoor "preview" of the tomb with themed lockers and torn-then-patched covering above it.
In the main lobby space, there would be an expanded and normal museum-style setting with a concierge desk and props from, again, the 1950s (this is derived from the general time period around the Streets of New York area). The normal queue would host a grandiose entrance to this new exhibit, with lots of "coming soon" banners placed throughout (both the singles and express queues will say things like "Special Guests Entrance" and "Individual Tours").
The story starts when guests see that the "coming soon" banners guarding the entrance have been burned and are still glowing along the edges (fiber optic display here). The interior of the tomb space is only slightly updated with signs (some half-finished) declaring what each element/artifact is, and what it meant to the pharaoh. The stairwell is remade into an elegant climb up to the "Main Tours" of the tomb, which now gives a story to the vehicles as well: "Your guided trip through the marvelous tomb of the great pharaoh!"
The ending is the main part that would be changed on the ride (besides using screens for animating the flying ghosts in the dark ride segments of the ride - they're on par with disco yeti), with a large section of smoke and rising projected spirits indicating that the haunting has finally left the museum. After a breather, a large themed wall with a huge statue shows a grainy black and white projection welcoming guests home with tinny triumphant music playing. However, at the last second, a shadow crosses in front of the projection, and a deep rumble is heard alongside a dark groan.
The exit queue is, of course, still themed to an upscale museum with a tour through the rest of the Egyptian section, and an "optional" exit through the Sahara Traders gift shop, which now boasts a more wholesome theme, as well as a "Wanted - Missing" wall full of people gone missing from the attraction (the ride photos wall).
Idk. These things just constantly bounce around in my head.