I think that an html5 build would help you get a lot more ratings. Especially since this seems like a very lightweight game.
As far as gameplay goes, making the player slide around a little bit when they stop moving might make it feel better, as well as a walking animation.
Some game juice could add a lot to this. Here's a gmtk video with some tips
Also, I don't think you are normalizing the movement vector. This means that you can move faster in the diagonal directions.
I like that you are using pathfinding, but drawing the pathfinding path can give away the position of off screen enemies in some parts.
It says that the faster you are moving, the less damage you do. I think your game should have some visual feedback that indicates this. Maybe make your screen shake a little bit less, a little bit less blood comes off of the enemies, the sound effects are a little bit quieter, etc.