Some suggestions would be some sort of health indicator and let the enemies shoot themselves, because I think it would take more advantage of this mechanic. If you added enemy varieties that shot different ways you could go far with this idea.
Viewing post in Rigged Control jam comments
Chouette basically covered what I was going to say. All I will add is that I think there are 2-3 waves where the enemies can actually shoot themselves, as I tried to somewhat take advantage of the mechanics with the little time I had left.
That said, you're right. There's definitely more we could've done.