Darn! Good job! I played a lot of fast-paced action title, and this game has both the vibe of "Hotline Miami" franchise and "My Friend Pedro".
There is nothing to say about the gameplay because it is really good and explosive!
Something to improve (in my opinion). I also played without using the time slow mechanic:
1. The combat is almost 100% smooth, but because of the delay when your character first touchs a wall (with the cloth animation), it somewhat makes the flow of action more sluggish and interupted. I died a lots because of that (missed timing to press space).
2. The bullet/projectile should be highlighted or more clear to see.
3. Change the color of your game's page. I can barely see any word :D
Overall, very new and unique combat style for this genre. I hope to see a full game in the future!