I haven't played this game, however I did judge it based on the video.
SUGGESTIONS:
1. Add more particle effects. Example: Enemy Death Effect, Running on ground, and Enemy Attack Particles.
2. MORE Animations, which is a small detail; adds a positive atmospheric feeling.
3. HD Texture Streaming as well as consistence on sprites.
These are MY opinions, and are given as feedback not to harm your morale, etc.