In the actual state of developpement of that game, I cannot really give it 4 or 5 stars sorry. Bring us that update, and if it really improves the game, then the rating will improve as a result.
This is a great game, but there's still some things that need some work. I think the zombies with guns are overpowered, when they knock you on the ground when there is many of them, you can already consider your mission as a failure. The controls system is original, but ho many times did I die because when I simply wanted to run from a horde of zombies, my character is getting closer to them because he prefered to keep a distance from the cursor rather than with the zombies.
Besides that, you've done an amazing work man, I like this game, there is just some things that are quite frustrating. 4/5 for now, 5/5 as soon as there is some fixes.