I really enjoyed the idea of a tower defense where the player needs to stay actively involved instead of simply placing towers and watching everything happen. Having to interact with the enemies while also thinking about tower placement makes the waves much more engaging and gives the genre a fun twist. The timing mechanic also fits the limitation really well. One thing I would improve is the feedback for precise timing: making a Perfect hit feel noticeably stronger or more satisfying than a regular hit, through extra damage, effects, or sound, would make mastering the mechanic feel even more rewarding.