I don't see how the game you have uploaded relates to how you said it fit the theme.

On its own, it's a solid start to a tower defense.

I struggled to figure out what were the differences between the towers. Flavor can really help the player intuit the differences between towers. 

I also had trouble with towers that shot too slow to even hit the enemies around stage ~5. I could have mitigated this with better planning if I had know projectile speed would be that relevant.