I agree with others saying there is room for improvement, but I found it simple and plenty enjoyable. Obviously there is a lack of visual style, but for me it would just be better if the game got more challenging. You could try adding more black holes as the player progresses, and maybe they start off slow and get faster, etc. I also think that with black holes you have an opportunity to make gravity a factor. Perhaps there can be big, slow moving holes that you have to struggle to move against, and little holes that exert little pull but move very rapidly and erratically. Still, I enjoy this and find it has replay value as is. Good effort!