It was definitely an interesting game! I like the idea and think local multiplayer would make this even better. Using the different classes to do different functions was sweet. I tended to just use the janitor and mop a few areas then get into outfit to rip and tear the zombies up!
There were some cases where I shot near a zombie and it didn't count as a hit even though I was directly next to it and my sprite showed I should've hit it. Whenever this happened I usually was stunned for the 3-4ish seconds from the shot and died. I didn't like the shotgun shot stun very much; it felt like whenever I shot I was taking a massive risk. But because the other soldiers died really quick I had to take on the hoards myself.
The difficulty of playing it alone was a lot, after a few matches I stopped because I was dying really fast and often due to the shotgun stun. Which is why multiplayer would be great since your friends could take on the other functions and make the game less difficult.
Overall, it was fun and with some tweaks could be a really fun wave game!