I'm gonna give you some good, harsh CnC, because you just started this style and you need it . The background is way to bright and plain,give it some contrast. The lens flare is OK, but put it where you focal is, I'm assuming you didn't want the area where the gun starts to be the focal .Text is nice, just a bit too faded. Nice distortion effect and the arrow vectors were a nice addition.
i do like the grunginess i have to say. but.... the orange light on his helmet just doesnt fit in. try a gradient map that will blend it, then erase all other parts of the map except the part that changes the orange part of his helmet. secondly, like rabbitt said, try blending it a little more. you did it well enough that when i look at it i dont automatically see the render/bg diffusion but they still look kinda separate