Impressive. I won't even get close. My setup is attached, but after reading this thread I realize I concentrated on the maze too much.
I'm not sure if I play this level again after finishing. It takes so much time and it is very boring. I fell asleep a few times while playing and ending up with loads of cash and losing a few lives.
I can't wait for new updates. It would be nice to have a "speed up" feature. This should come with a frameskip, because my iPhone is having trouble with a lot of enemies and firing already.