Here's two paintovers. as you can see, rim lights are helpful in pulling the figure out of the background. I've also darkened the background some and you should make sure you are thoughtful about making the figure clearly lighter or darker than the background. You also have a bad habit of doing blown out highlights that have an atmospheric shine, it muddles your values and makes things less legible. You need to learn the difference between a plane in light and a specular highlight. Most highlights are darker than you expect, and requires value control, speculars are quite light, but are typically harder edged than you'd expect, especially on metal. Lastly I sort of did a little drawover on the arm of the spearman. You should study analytical figure drawing if you can, as you were lacking form in that arm. Think of the arm at it's simplest as two tapering cylinders, it makes them easier to draw in perspective. Keep working at it.