To make the game more interesting, you could implement new mechanics as you advance. The light mechanic seems interesting, but it won't save the game by itself. I'm guessing you didn't have enough time, after all, it's a gamejam.
The atmosphere was pretty well captured, and the sprites were nice. The only thing I would say is that the jumping animation should be quicker at the beginning, because it feels like it's reacting too late, and you probably want your players to feel total control of the character.