Honestly, the idea was there! I managed to reach the fourth level (fun fact you can jump on top of a pillar in the third and attack from safety the enemies, probably the most fun thing i did) but then it became too overwhelming to fight back. I am not entirely sure what the platforms were for in the fourth level. During my first playthrough i did not realise that enemies dropped power ups, maybe they could stay in the stage for a little longer before disappearing?
Since there's no dodge or guard button maybe you could try to allow attacking while moving, check out my game as well since it's a hack and slash too!