Suggestions
If i were taking this project over, I would first make thee circles animals. Then, instead of all the red dots killing you, the smaller ones could just hurt you, so it takes more than one hit. Once you make the circles into animals, I would let the user pick what kind of animal they want. Then you could change the predators into the according creatures. You could also maybe add powerups or something. Maybe have more green things and not have them worth so much. Maybe obstacles instead of an open field. You let them be levels, or have the user pick a level to play on. Hope this helps you