The game is AMAZING, i loved every part of it, it is tough to make a game where you try to make the player invested and not bored immeadiately, and you excelled in that part! i didnt even notice the time passing of how much fun i had playing this game, from the variety of enemies to the variety of plants (defenders) it was pure fun and well made mechanism.
suggestions:
The game felt in need of more SFX, such as an indicator of when the wave is done. and maybe making better audio for the impact of shooting/being hit
also it would be amazing if it had more animations, such as a walking animation and also some movement to the enemies and lastly the tree itself that the player is defending.