There is a good foundation here. Here are a couple critiques:
- Add juice! Juice alone would improve the game substantially
- Increase the hitbox size for the player swing, I feel like I missed bunnies when I shouldn't have
- Either add a healthbar for bunnies or make them all have 1 HP
- Introduce some stakes into the game - right now I can just choose not to kill bunnies and nothing happens. I think you could add some time pressure or other incentive for killing bunnies
Those are my opinions, with a couple of tweaks this game could be a very fun arcade-style game!