I'll do some minor CnC on your Death the Kid signature because I'm not in the mood to fully critique it.
To be honest, I like that sig a lot.
Your lighting need a good bit of work though (the depth is great and you have some pretty decent flow, the effects on the tip of the gun make your flow a bit messy, but I understand you didn't want to leave that area blank because it would've looked empty :3)
It seems you got the main light source identified, and you did a great job of showing that there's a definite light source. The issue lies in everything else though. The random dots of light on the render were a bit necessary and take away from the lighting aspect. (mostly the dot on his hair messes it up). Also, when thinking about lighting in a sig, don't think about just the light itself. Think about the shadows that help contrast it and bring out the depth more and intensify the lighting. That's what truly makes good lighting, some shadows to go with it. So what you should have done in this sig was get rid of the light in the bottom left corner and replace it with a darker C4D, then add a large soft black brush to the edges of the sig (minus where the light source is) and then lower the opacity. Make some smaller ones on higher opacity too if you want to make your shading more detailed. Sorry if you don't understand this through words, you could look at my GFX examples to see some shading in the corners if you're confused.
