We wanted to add audio, but we ran short on time sadly. In terms of shooting and levels, it wasn't really a part of our vision for the game as it is really meant to be endless, and the whole idea is that the player is just dodging and surviving instead of eliminating.
I appreciate the feedback for the controls, though it was a very low priority for us as we display the controls right from the start and they are fairly simple (movement controls are standard and we only use one other button). We really just wanted to get the game to a playable and enjoyable state before we worked on the finer details, and unfortunately we just ran out of time for a lot of it.