Quote - Even in a smiple three point setup, the variables are large.

that is an understatement :) 

Lighting is one the most crucial elements of the scene, together with composition and framing. 

If you are struggling with lighting I suggest to simplify. Three light do present a lot of variables. So, use one mesh light only. Try to make ten renders with only one mesh light in the scene. Set it on the side of the subject. Then move it above the subject. Scale it bigger, way bigger, or smaller. Try all these and other variations, you will learn a wealth of experience in lighting. Once you are confident with the results start adding a reflector, not another light. Just a reflector, which is a white plane set to Glossy. Make sure that the reflector is opposite to the light, facing it and being oriented toward the subject. 

Compare the difference with the same setup but with just the light.

Hope this helps.

Paolo

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