Cool entry!
I think the visual effects look nice, and it's cool that you got so many entities to run pretty well in a web build. I also liked the perspective, and how you can see another chunk of the planet further down that has more bugs on it. It really gives the game an invasion feel, which I think works really well.
I think the game could benefit from having some sort of onboarding, even if it's just a text box at the start. This could be extended to making the bugs appear more slowly at first, and the game ramping up over time. I was very confused (and I think I'm still kind of confused) because I don't think the game explains very well what's going on. I didn't really get a sense of how well I was doing, or what was happening. For example, I didn't know what the different bugs did (at the start I was very confused as to what I was looking at), I didn't really get what the upgrades did or how powerful they were, I didn't know if I was winning or losing. I think this could be a very cool game with some more work on the game design side of things, so that the player doesn't feel super overwhelmed and can make more meaningful choices.
It also feels like you level up way too fast sometimes, as if the different upgrades make you more powerful but the xp required to level up doesn't increase, so it felt like I was hearing the level up sound faster and faster every upgrade.
Speaking of, I wish the game had more audio! It feels like there's a lot going on in the screen, but you don't really get to feel like that because there's no music or sound effects for the actual combat. I feel like that would go a long way to sell the player on the invasion feel that you already have working pretty well and getting them invested in the game.
I hope you continue working on this, cause it has a lot of potential! Keep up the good work!