Nice to know the phases feel varied, I was a bit worried about that since the gun and machine gun phases are almost the same thing. There was a plan for becoming able to switch gender at the end of the life cycle on later levels, and the female forms having different attacks, but it was too over-complicated and time-consuming. Once of the 2 planned attacks was given to the final boss, the gravity bullets, to be precise. The other one was summoning drones that would follow you and shoot at the boss at random intervals.