Robot Birds and Razor Blades

I've made a couple more levels in my scrolling shooter game, but for now I'll just go over what is currently the 5th level. In this level, the enemies are robot birds. There is the "Layer" class and the "Boomerang" class of minion. The Layer gets its name because when it is killed, it leaves behind (or lays) a robot egg pod thing. The player must kill this also or in 3 seconds it hatches into a miniature version of the Layer called a Hatchling. With the Boomerang class, their projectiles are quite unique for minions in the game. They shoot out their spinning razor blade bullets, which go out to a specific distance from the bottom of the screen and then hook back and leave the screen at the top. Basically the bullets follow a tight, long U shaped path and if you aren't paying attention, you can get hit by the returning bullet that you previously dodged. Overall I'm pretty happy with this level. The enemies are unique and it is pretty challenging. Right now it is only level 5 (I want to get at least 10 levels in the game upon release) but I think I might have to move it back to be later in the game on account of the difficulty level. Below are some pictures of my crappy MS Paint robot birds (the background is my crappy test background