Apparently Mr. Nomura loved the latest incarnation of Les Misérables so much, that right after he saw it, he wanted to turn Final Fantasy XV into a like-minded musical.
E3 2013: Final Fantasy 15 Was Almost a Musical - IGN
So how would you have felt about this? Honestly, as silly as the idea of a musical Final Fantasy game seems when you think about it, I think, if done correctly, an RPG epic in the vein of a Final Fantasy title, done in the style of a musical, could be something great, and something I'd definitely want to play.
Imagining Noctis and his cronies along with those two old dudes bursting into song and dance mid battle is pretty hilarious.