I love the "light distracting monsters" mechanic! It was difficult navigating in the dark but the heartbeat indicator was nice and intuitive. If you were going to keep this idea and expand on it I feel like a slower progression of "levels" so that I could learn how the monsters behave would have been useful for me.
Edit: Specifically the thing that made it unclear to me was that some of the lights were triggered by me walking close to them, so I was paying attention to controlling the light rather than the monster's behavior. Playing it again just now I can see that you did exactly the thing I was suggesting.