I, also, agree that the wall overpowers the figure
as painted in the picture, at least at first glance. Then I take a breath, and ask myself why I think that.
My old bonsai teacher once remarked that the the tree and the pot must work together to create the vision. But the first time someone says "Nice pot!", you know that the pot - its size, shape, color, decorations, etc. - is visually overpowering the tree, when the
tree should be the center of attention (this is always the case with bonsai, but with other art forms the intent may differ).
Same thing goes with figures, busts, vignettes, and dioramas: You have to figure out what you want to be the focal point(s), then design, construct,
and paint the item in ways to draw the observer's attention to that point or area.
What I'm trying to say is that, if we could get inside the artist's mind, we may find that they have a different idea what they wanted to emphasize, the point they're trying to make, the message they want to convey. It may well be that, in this case, the sculptor was looking to emphasize the smallness of the individual in the context of the larger environment, the disproportionate power of war, that humans have destructive potential beyond their size. The use of shading and "mother colors" can be a central element to (de)emphasizing any portion of an artistic piece, 3D or 2D. In this way, the painter has, to some degree, the final (general) say on what the piece communicates.
If, for example, the intended message is that humans have great destructive potential, the desired focal point might be the size disparity, the smallness of the armed figure vs. its surroundings. If so, the paint scheme might de-emphasize the figure a bit, and highlight the building damage.
OR, maybe the message is the power and determination of the human spirit in the face of harsh adversity; if that's the case, the desired focal point could be the figure itself, in which case the piece could be painted to emphasize the figure and push the wall into the perspective background.
So when I assess a piece like this one, I try to think about different messages it might send and how each might be painted, select one, and go from there. ALL THAT BEING SAID, I do feel that this piece, while technically well done, just feels a tad flat to me.
ON THE OTHER HAND, it may also be that the wall is just a little too damn big for the piece ...
Or maybe it should be a little bigger, depending on the message the artists want to convey.