I don't know "Waiting for the Moon", but both Tiffany's and Nick and Nora were solid ideas that were ruined in the execution. They both lost what is beloved in the material. In the case of Nick and Nora it was probably a bad choice to have Arthur Laurents as the writer/director--it's just not his cup of tea. The important thing in the Thin Man is the relationship between the leads and it was downplayed. Laurents can be brilliant, his book for Gypsy is possibly the best musical book ever but he just has no feel for the light charm of something like the Thin Man, though it has some good music and it was extremely well cast.
With "Breakfast" they never got a handle on what it should be--they probably would have been safest sticking as close to the movie as possible but they changed the focus too many times and the final book by Edward Albee (again, a bad choice for this material) was apparently really confusing and unpleasant. It's too bad here too because it also seems to have been well cast. I've heard Mary Tyler Moore blamed herself which is too bad. Once again I think it was a bad match of talent to material, Albee writes great, shocking, funny plays that make you think for days afterwards but he was a bad choice for "Breakfast at Tiffanys".
Yes, we do need a third vampire musical.--Little Sally, Gypsy of the Year 2005.