Comparison. Left is Anh Dang's original concept art. Right is my rendition with a few conscious differences

Looking into the distance.

The entire mesh was modeled using non-destructive methods using blender's modifier system. that means everything is completely and very easily adjustable at any point until the texturing process

For the details, created a Normals decal sheet using a separate file and some floaters, and baked that down with transparency. I also experimented with combining different parts together like in this example.

I created two very simple textures in SD. One for the grunge, and another for scratches, and exported them on separate channels into one texture. This allowed me to use one or a combination of both for the roughness and bump across the entire model