LogInChristopher Schiefer talked a little about the way he uses 3d and 2d tools to create outstanding images.
Composition and design:
Strict use of Symmetry. Repetition, Rhythm and making the subject as expensive as possible to achieve a stronger impact.
Additionally, I used Subtitles and a 1.85:1 ratio.
Green = Symmetry
Red = Repetition and eye movement Blue = Center
Yellow = Emphasis
Economic Management using scripts:
In order to keep everything organized in the 3D Scenes, I worked on 20+ scripts in my free time to reduce the work on importing and adjusting all meshes to be rendered faster and artifact free. Also, I recommend working on little add-ons for your workflow. Learning python is easy to do and the benefit is massive if used to speed up your workflow.
It makes a serious difference if you spend your time on your workflow. You are able to do more massive scenes with less iterations and Therefore you can produce more and more scenes!
Materials:
I came to the conclusion that in concept art we have to use procedural based methods to add variation on the base renders to reduce some work later in breaking up Flat surfaces.
I took the idea of Smart materials from Substance Painter and implemented my own version of it in blender. So I work on all Channels separately.
E.g Wet surfaces based on Normals and Dirt stretching according to normals. White and Black dirt.