Take this with a grain of salt, but i think that Japan's version might be superior.
The screen is not that curved. So I think 3d couLd absolutely work. 3d on an omnimax screen would look gorgeous.
The BTTF vehicles seem to be capable of more movement. Despicable me's simulators seem alot more stiff. IMO, Jimmy Neutron technology from orlando really didn't translate well to Despicable Me.
Also since you are in your own vehivle, the experience is not ruined by the sides of the screen.
Actually, no...3D does not work well on an Omnimax screen. It's actually quite curved.
The sizing and proportions would be completely off. I don't see how they can accommodate three levels at once while keeping the entire show in motion. They'd need to scrap the small preshow rooms but somehow get guests to the ride vehicles.
If they significantly zoom out and alter the footage a but, the proportions won't be too off, trust me. It's all in the formatting, and would depend on how extensive it would be.
As for the queue/loading, etc? No clue how they'd make that work....the flow would be off.
Then again, this is Japan. Maybe they'll be able to make it work and make it even more unique. Hey, for all we know, maybe this will be an all new Minion Mayhem, or they'll just at least create an all new queue. I wouldn't be surprised, Japan knows how to improve everything.
If it was strictly based on the current layout, I'd make the first part of the queue the "house" tour, with all the different monitors playing the preshow video we see in the living room over in USH/USF, and then as soon as the guests are being split into the 3 levels, that's when the rest of the queue will become Gru's lab.
They can then make the "midway" queue holding rooms the room where we "meet" Gru and the girls, etc etc.
It'll be interesting to see what they can come up with.