Let's trade feedback! I submitted too.
Mechanics: Cool concept overall! I like that you have to manually refresh your towers. I was surprisingly challenging. On top of that trying to dodge enemies and be aware of the bars----It's a balance to win. I think you could introduce scale to your game better. Start out with a smaller intro map, then the map grows with each wave. An intro level would help players adjust to the controls and also how the towers work, before getting swarmed by so many enemies.
Visuals: Good use of the pixel packs. I think the map has good structure and consistency. It is troubling to have enemies off screen that I don't know about after a while. I didn't know enemies were attacking my northern tower until it was too late. Going between the towers is hard when they're so far apart.