IMO things that can be improved :

1. The pic has no horizon or objects in the distance. This makes it very hard to judge what the scale of the pic is. ie are those real graves or models of them on a table top somewhere.

2. The placement of everything is too random. Not only does this make for bad composition, but IRL cemeteries dont just plop down the graves anywhere. They have an ordered structure that you should look for in refs.

3. Shadows in scene. A situation like this can be helped a lot by having some nice shadows. Makes the cubical forms pop out more and goes with the spooky theme.

4. The light from the right/behind is a warm orange. Given how cloudy the scene is (and actually looks like night) where is this warm light coming from ? You almost expect a lit torch or a fire nearby casting that light. But no such light source is visible anywhere.

5. The trees are very distracting. Unless the focus of the image is the trees themselves, you should change their look and/or add DOF blur to recede them into the background.