Not too bad..lol
Work on that bg, it looks mix matched. Transition it smoother. The light FX aren't really complimenting your render.Arrange it to match the render's flow. Maybe try a diff blend mode on that smudging to screen or something. It looks kinda dark and smothering on the render. I like that text, but it's too far away. Placed closer to his shoulder would look much better i think and sample colors from the sig for the text so it blends better.
Lastly, watch the depth. It;s over sharp on some parts and over blurred on others.Instead of brushing the blur, maybe try a gradient blur so it's smooth.
Like i said, not bad..it will get better with more practice.