Go see RAGTIME. It's a better musical, in my opinion, and to be able to see a professional grand-scale production, at the Kennedy Center nonetheless, is an opportunity I wouldn't pass up!!
Also, I would suspect that if NEXT TO NORMAL even gets to the same fanbase size as PASSING STRANGE, then it will be open in September.
NEXT TO NORMAL is a great show, and a superb ORIGINAL show -- one of the best newly written & produced -- but not THAT good to miss out on RAGTIME, in my opinion.
"The Spectacle has, indeed, an emotional attraction of its own, but, of all the parts, it is the least artistic, and connected least with the art of poetry. For the power of Tragedy, we may be sure, is felt even apart from representation and actors. Besides, the production of spectacular effects depends more on the art of the stage machinist than on that of the poet."
--Aristotle