After different approaches and failed starts, I knew I had to work with shading and creating texture to rocks. I feel that I was not making any progress due to my inability to create texture to the sandstones and the cliffs. As evident to my first rendtions, the textures were sub-par. Due to that, it was hard to create perspective from the rendition. It was hard to determine where the light source was and it skewed the perspective of the work.
I've researched and watched other concept artist their workflow and their procedures to work on this. I've noticed that the using the right brush really mattered and that concept art is not about time spent on details but rather clever usage of textured brushes and using photo textures to blend with your work. It creates a much realistic art style and definitely is time efficient. After all, as a concept artist, time is precious to you and the more you can produce the happier your client/team will be.