Keep Moving Forward
Sounds very interesting. The plot reminds me of Trolls a bit. Here's why:
Also, because this isn't really a musical, it could be like Toy Story where the story is told through songs played in the background. I once read that this concept originated from Disney wanting to have the characters in Toy Story sing thanks to the success of their recent musical films at the time (The Little Mermaid, The Lion King), but Pixar refused to have that, and they compromised by making the songs the way they are in the film today.
In both films, there's characters who don't like singing because it related to someone's death.