I played it on medium, hard and very hard mode. The hard and very-hard are just impossible to play. On the medium mode, I did clear several levels, but quickly stopped playing because there is no satisfaction in clearing the levels.
The game can clearly help with some VFX or SFX especially when you collect the scrolls. And what does the scroll do? I think it will make the game better if collecting scrolls give you hint on where the exit is. Or the scroll can give you some power to repel the enemies. At this point, the game is only about luck on whether you find the exit or not.
Since the tone of the game is dark, I am assuming you are going for a horror feel. If that is the case, you can put some SFX or some blood markings to make it spooky.
I am sorry if this sounds harsh, but the game at the current state is a very inferior version of Pac-Man. It has similar structure but without the fun and very limited visibility. All being said, I hope my comments can point you toward which improvement to make. Best of luck!