I can read that you didn't get to add music/ SFX/ quest with another ending/... because of time, I would suggest to try prioritizing. Make a list of what is necessary(1 song/ 5 characters/ ...) and what is optional but would make the game better (for example extra characters). If you have implemented all the necessary things, you can start working on the optional things. That's just my suggestion for time management.
Otherwise, I find the characters and dialogue really creative. You guys are doing great, keep making games!