This was pretty cool! I like the artwork, animations and gameplay loop! I could see this becoming a rougelike. It be cool to see you polish this between mini jams.
As for critiques, i would love a small arrow pointing where my mouse curser is. so I have a better idea where i am aiming. also when the game starts, I would like a practice mode without any enemies so I can get used to the controls before starting wave 1. It also a good idea to list the controls on the page to give the player more of a chance to familiarize themselves. And as a side note, music would be nice. but i suspect there wasn't a composer on hand.
All in all, a fun arcade game! I wold love to see what you do next!