Feedback received from Tumblr.
Feedback received from Twitter
A common suggestion from both social media sites included darkening the film as a whole in order to achieve a horror film feel as this would help convey the themes of the film.
Another point suggested is why the killer is doing what he is, in both Feedback sections this point was raised as people thought this would help the story 'depth' and also clear up the storyline that could be missed.