I know that it is a popular topic re: Disneyland and hopes/dreams of new attractions pop up as a thread periodically, so I thought of posting my take on what could be done with the USH property.
Now that GE/NBC owns the parks, and they are not exactly poor, they could fund some truly amazing attractions for USH and really elevate the place to greatness. Mummy's Revenge looks like it will be a fantastic start, so here is my humble opinion and open suggestion for improvements for USH.
My idea would be radically alter Backdraft. Essentially, the attraction tells no story, and in movie based theme park, that is a problem. So here is my premise, cross Backdraft with the Tower of Terror.
To elaborate. The set-up could remain similar, three stages, with the third being the explosive finale. But, the story would now change to engage the audience. My premise is that an arsonist is loose in the park and is determined to burn it down to the ground.
In pre-show area 1, the lights cut out and the audience hears footsteps above them as the fireman are looking for the "Arsonist". The power is restored, and the attraction host gets a frantic phone call, apologgizes to the audience for the interuption, and escorts the audience into the next room.
During pre-show two, the arsonist now busts through the ceiling, drops down onto floor, introduces himself, engages the attraction host in a bit of menancing banter. Our hero, a fireman, follows down through the hole in the ceiling. Arsonist escapes through the back. Fireman tells audience that everything is under control and then chases the Arsonist out the back door.
Then, in the third section, things get interesting. Guests sit into two tiered rows, with locking lap bars for their safety. After the host/ride attendant makes sure everyone is safe, the power cuts out again. Arsonist comes through, promises his captive audience a real show, and runs down the catwalk, down a firepole onto the main floor abour 20 ft down, and out through a side door.
The lights malfunction, steam pours out of the ceiling, seats shake. Guests see search lights come through the ceiling looking for the arsonist, but the next thing you hear is "it's too late!". The fire show begins much as before, then all of a sudden, the ceiling gives way and the Arsonist falls through (a dummy) and crashes through the floor in a fireball, out of site. Then, explosive climax occurs and instead of the floor dropping a few inches as it does now, the seats drop 30 ft down into a 10 ft pit (assuming the guests seats are 20 ft above the main floor, 10 ft. below ground).
Instead of it being over, guest see a fireball coming towards them (steam and red light), and the chairs are shot up 60 to 70 ft, breaking through the "ceiling" of the stage, then down, then back up to the 30 ft. elevation to exit the attraction.
Obviously, it poses some techincal challenges in having a launching/braking system with rows of seats, among other issues, but after seeing the stuff Universal Creative has pulled off in the past I'm sure they could solve those problems.