This is a good start, I can see a lot of potential in it. As other mentioned, the movement could be sped up a lot and I like the idea about the slot usage by keyboard. These two would greatly improve the overall experience. Also, probably multiple shots could be used if I want. However, what is the point of the multiple weapon types? The main enemy can be killed after collecting 20 bullets which gives you the sniper and that is much-much better compared to the others.