Loved the concept of this. I wish you all had the time to flesh it out more. I know you had consider procedural levels which would have really worked with this type of game. The games visual have a charm to them, love the little cat driving the sub :3
I think a few things would have gone far though: audio effects, an enemy type or moving obstacle, a second level, in level instructions, a reason to use the cool laser. Obviously these are things that I'm sure you all could have gotten to with more time though, so great job nonetheless!
Lastly just want to say that the controls are nice! It makes you really have to balance your speed vs the risk of crashing into things. Good job!