As much as I love musicals I've never once seen a Broadway play in-person. My knowledge is limited as sad as that is, although I always thought if my comic got turned into an animated film or something by some blue moon, having it being a musical would be sick as hell.
Honestly the only one I could compare it to would be Les Mis or (1938) Gas Light, since they're the most similar plays I can think of, despite the latter not being a musical as far as I remember. I couldn't say what the style of music would be since I lack the experience to know, but the songs would probably be mental health related, stuff that would move the story along, Julian's "I Want" song probably won't come about till halfway into the show, Apollo's a third or forth of the way in. There will probably be a lot of sad music, stuff like that. A rock opera would be pretty awesome if that could be pulled off.