Not a bad attempt here, well done dude, the blue suits the render
but here's a few things:
-It looks like you've used just one c4d, and duplicated. You should always try to vary the tag, use parts of a c4d that look completely different, or entirely different. Also, try to use ones that have more then one colour, or the tag ends up a tad too monotone.
Always try to pair a colour with it's opposite (i think that's the word) Of the top of my head, blue would be orange. It's always nice to mix warm colours with cold colours to create a balance
Another thing is that light. It's just, wrong. no not wrong, inconsistent. The render has shadows on the left side of his face right? And on the left side of his neck. would this really be created by a light source on his left? I don't think so.
Always take note of the natural light on the render, and play to that. or the depth just seems wrong. Lighting helps depth. Remember that