Proportion: certain objects are smaller than others to create depth; the objects are all relatively small and proportionate to each other.
Composition: bolder colors seem to leap off the page, whereas lighter colors appears to fall back; almost all the objects are vertically (or almost vertically) placed so the eye travels up and down when looking at the piece; there is balance of shape and color.
Answer will vary for the artist's message but should be backed by reason. Like the artwork is inspired by what is happening in the life of the artist; what is happening in society, or even what universal truth the artist wants to impart to his/her audience.
