Even though it was nearly 50 years ago, I still think the Apollo 11 moon landing would be an impressive scene to try and replicate with a diorama/AA setup. Conceivably it could be accomplished with a minimal combination of stage props and projected backdrop, like the Valley Forge sequence. Use Kennedy AA at lectern giving the "We choose to go to the moon..." speech in the foreground stage right or left, with the lunar module descending main stage onto the moonscape. Then use the starfield backdrop as a transition to the finale film. Sure, it might feel a bit repetitive to have two presidents at podiums in the span of five minutes, they'd have to find ways to distinguish the two.
But I'm sure that a refurb like that would be much more along the lines of a six-month (or longer) job than a one-month timeframe. Sounds like new screen, projectors and finale are all we will get here. And that's not too shabby.