Too much absolute black in the interface picture. Try using various shades of gray in order to make it not look like it's super flat. Also, you can crop off the right and bottom parts of it and still have the same image, since Soldat anchors pictures from the upper-left corner. Don't use Paint's built-in .jpg conversion next time. It fubars the picture, preventing it from actually being used. Convert it to .png instead, lower filesize with the same quality.
The interface picture looks good (apart from the absolute black problem).
The in-game picture doesn't look enough like the interface picture. It looks like one of those guns with the grip in the stock (i.e., AWP).