i think this game is good but i have are a few ideas you could use #1 you could use a difficulty setting like easy, medium of hard #2 it could start at a slow speed and gradually get quicker #3 have some sort of power ups like slow motion, 2X points or no walls #4 you could put some music on the game
I find that banana research facility's are really useful because after you get one you can afford more and more, then when your bringing in 30k a round you buy loads of super monkeys