Great range!
The music and sound effects are good, but your story progression is slow. It is a little cliche, but that's how most apocalypse stories are. The voice acting is good, the characters are just a little bit too calm (obviously they are taking a risk by attacking the city, so I think they would be more worried). As stated above, your range is great, I can easily tell the characters apart.
If you do plan on continuing the story, I think your best bet would be to have the good side lose, because if they win, this is going to be too cliche.