An update on my JS-2 diorama: Here are some photos of the first stages of painting for the base.
I started by painting the individual details with plain colors (no shadows or highlights). I also worked a bit on the rust effects. The corrugated panel in the center of the diorama is more a test than anything, since it will be entirely hidden underneath the tank.
Then I used the airbrush to start simulating brick dust and give some hints of shading.
Next step will be the washes and pigments.