I voted Mission Space because, of the choices offered, it would fit a tomorowland theming without more cartoon character/ movie tie-ins better than the others.
But actually and personally, I think as others have said it would be better to have some original idea.
That original idea I also would like to see utilized in the new attraction should be themed towards space travel or environmentalism. Yes, environmentalism, because hopefully in the real world of tomorrow we will be using resources like solar power to produce electricity rather than just burning fuels (ethanol, coal, oil by-products, etc.).