LOL. You're not the first to say that

The pavilion you mentioned was what we were competing against, and it was rejected by WDW and the project was shelved. Our proposal was a reaction to that because they explained the kind of more thrilling show they wanted, put a check on the table and there were no takers. Susan Bonds, the producer of the shelved concept came to me and was upset saying that there is still a chance and would I partner with her to try and save the project for WDI. I didn't like the notion of being in a "Space Station" filled with tourists and real world "exit" signs that blew any realism you could achieve. It felt very theme park. How could you really give the impression of real Spaceflight. Epcot to me had to tell the more science oriented story.The more personal experience of the extended G Force capsule idea was born in Horizons and we sold that almost instantly.
In some aspects, I agree with your critique of MS (I don't think it's "easily one of the worst"), I would have handled the graphic quality and story very differently if I had the authority to do so, and the post show could always be more (but almost was even less). Truth be told, the producers did a great job getting more into that show than management wanted via Compaq. Susan Bonds, the producer (and later Larry Gertz) made that bigger show happen by sheer will. But the capsule is tight by design and meant to be that way. Space is not luxurious and we were trying to deliver something realistic and intense, not typical of theme parks. I sat in the real Shuttle and pressed the buttons and it's like that. I'm VERY claustrophobic myself and maybe it would have been better if the media had a "heads up" grid or cross hair gyro graphic to give you a horizon line so you don't get sick. Simulation without reference points gets people disoriented. The capsule show I was pushing for was more spiritual (2001-esque) and not as action packed. Less dependent on spinning and disaster. You may have hated my "directors cut" version even more. We'll never know.
In the end, it's a "love or hate it" kind of show. In rebuttal, I think it's pretty cohesive in that you are in a "trainer", not really going to Mars. Having a breakthrough ride system is a big deal to me as IMHO it delivers on the unique feel that vertical liftoff has, extended G forces. I'm pleased with the overall project because
I think it does fit into the EPCOT mantra very well, but there are, as I said, things I would have done differently. So what. I'm sure there are things the producers would have done differently too, for lack of funds or other reasons. We'll never know. The unbuilt pavilion concepts never suffer budget cuts and always have the unfair advantage of being a wow in our imagination! Paint never peels in our minds eye! Good critiques just the same.