It looks very pretty! I don't know if you have implemented a (however simple) particle engine but from the video I don't think you have. I highly suggest you do that as it adds a lot to the feeling of the game. Imagine having some nice white to blue or white to orange particles as the ship's jet instead of an animation! It would be very cool. You could also do a simple blend function using glBlendMode (I think that's the name) instead of implementing color changing. Maybe add some ambient particles as well and you have yourself a VERY beautiful game. I also really like like the way the ship rotates
. Overall very nice job on the game, looking forward to seeing a demo!
Edit: I love the textures, maybe use a shader to make the "seaweed" move/jiggle around a bit? Check this out: http://www.raywenderlich.com/10862/how-to-create-cool-effects-with-custom-shaders-in-opengl-es-2-0-and-cocos2d-2-x