I think this is a strong base. The controls feel effective for the task we are given and I love the simplistic art style and changing colours. I would say some audio is needed via sound effects or just a simple looking track, would really add to the game.
I'd say from this point you could really look to build on this base with different enemies, shooting types and add some move complex elements.
To be honest, I like it. Even if it's just shooting squares, there's a lot to it that makes it fun. :P
I am sorry, but I simply couldn't get into this. It was just a ship firing over and over. I was confused as to how to play. There was just no variety. I didn't hear any sound either. Maybe there was something wrong with my laptop? This was just so bland.
It was hard to see any point. It was just the same thing over and over. I did go from 2 to 18. It's just hard to be motivated with this. It needs a lot more detail.