As for the set design issue, the Shaw Festival did a production in about 2003 or so that used minimal scenery on a small stage in a small theatre, and the show still worked. It may not have worked wonderfully, fabulously, brilliantly, but work it did. By the way, the production was unmiked.
A good show, one that is strongly written, can be done on a virtually bare stage with only the props absolutely called for in the script.
The original design was wonderful, but it isn't a deal breaker.
I do hope Roundabout stays clear of a new production. After Bye, Bye Birdie they ought to shut up the musical department.
"If my life weren't funny, it would just be true. And that would be unacceptable."
--Carrie Fisher