I wouldn't call this 'dreadful', but I would say that N+A are not really good musical theatre characters nor is their story one for a musical.
They and their lives and their setting is that of grand opera. A musical would trivialize their tragedy. An opera would set their fall to scale.
Whoever is writing this work needs to rethink their piece.
"If my life weren't funny, it would just be true. And that would be unacceptable."
--Carrie Fisher