I tried your game. It's obvious that it's in the beginning stages so I'll spare the games simplicity. There's a few things that I would recommend.
- Shots to the head are instant kill, if not 2 shots in the very least. Zombies shouldn't die to body shots as fast as they do.
- Different audibles from the zombie and player character. Hearing "ughhhh" every shot is annoying.
- Game loaded in a black screen and changed once I fixed my resolution and graphics settings. Not sure if that is fixable.
- Different death animations. Currently all models seem to fly in the air?
- Recollect Arrows. If an arrow is shot and hits, I should be able to retract it from the zombie.
That's all I can think of at the moment.