I liked it. This is an interesting concept that might worth explore more.
Some things to consider
- what if you would only see ghosts if they are kind of close to you when outside of the light. this would make them more scary
- what if we could use the light to explore bigger part of the map without moving the character. like when the light is on the right edge of the screen you would scroll the visible area to the right. this means that the character might go outside of the visible area which is risky but can give you more info on the level structure