was this the correct format for this movie?

Since EJ didn't write the lyrics would it have been better to just do a straight up biopic as opposed to a musical where they try and show the inspiration for his songs through events in his life. I understand that BT was inspired by events in EJ's life for some of his lyrics, but this movie is through the eyes of EJ. I think they were caught in between making it a darker movie about rehab/his life and a musical that was more entertaining. Overall, I did enjoy it, but it felt empty.