>Is a revival of "Boeing-Boeing" really necessary?<
I don't know about necessary, but anything that brings Mark Rylance to Broadway is entirely justified. It's a play that was always a huge hit overseas and never fared that well on Broadway, so it's not exactly an overexposed choice.
>"The Country Girl"?<
We get Eugene O'Neill, Tennessee Williams and Arthur Miller revivals on a regular basis. Why not the same for our other great and less frequently produced 20th Century writers like Clifford Odets or William Inge (Come Back Little Sheba).
I can't quite rush to the defense of revivals of The Ritz or Old Acquaintance, but one never knows when a combination of actor, director, production and revival choice will catch fire. I remember Lincoln Center's decision to revive that hoary chestnut The Heiress met with some raised eyebrows, but it proved to be a sensational evening.
Color-blind casting is a whole other question, but one of my favorite productions I've ever seen of Fiddler on the Roof was with a black Teyve. A great actor can make you believe anything, and matters of skin color become immaterial.
Begin at the beginning and go on till you come to the end: then stop.