Agree with another commenter about camera height. Couple more things.

1. Your demo level suffers from Z-fighting in a few places on the floors and walls. https://en.wikipedia.org/wiki/Z-fighting

2. When viewed full-screen on a 4k monitor, textures are too low resolution. A handwritten note on the wall is unreadable.

3. Lighting is too simple. Because that’s not an FPS shooter you probably don’t need dynamic lightning nor day/night cycle, but it’s still hard. Ideally you need these multiple PBR textures everywhere, and correspondingly complicated pixel shaders.