i think some ideas could be input to the game majorly. some progressive (unlockable) abilities, possibly boss battles (more than what was just seen in the film), secrets (or secret boss battles), unlockable characters, like the "jumpmo" you would see in the film (spoilers btw sryy). If you need help developing i can help, i dont have much experience with game developing at all, but i need some more knowledge and expertise before i can start making my own games. i am able to make alot of good ideas for games though, being a "natural at theorycrafting" (my friends say that).
edit: i just saw it uses godot engine, but i use "gamemaker studio 2", so if you do end up accepting, im fine with switching dev-tools
if you do end up needing another developer, my discord is "The Game Squad#8371" if you want to contact me