Lawrence, in regards to your perspective, you can move the central line of sight a bit more to the right so that the angles of the beams don’t mirror each other as much (see what I posted). Also, pose your characters in the foreground better. They need to read clearer. For example, take a look at the guy closest to the camera. Move his head out of his coat so that his profile reads better.
The ceiling feels flat because it needs texture. Add more info about the condition of the surface. Tell me more. Maybe there are things hanging from the seams.
The background area needs way more clarity. They’re way too ambiguous. Make sure the shapes read better.
In regards to your painting, be more careful with edges!!! Everything is too soft. Be more mindful of surface on the form and how it reacts to the light. For your color palette, stick with a complementary color scheme (for example, blues against orange.) This will add to he feeling of tension in the scene and reflect the mood.

-Nino