Good stuff!
A couple of suggestions.
The transparency cutouts now show the underlying terrain texture. Given that matting was laid on graded, prepared ground, it looks odd to see green through the perforations. This would pretty universally be soil. Which militates against the use of transparency cutouts unless the ground tile underneath is more representative of dirt.
Even fairly old matting has a more neutral steel-grey hue, certainly so while in use. While there can be a certain amount of dirt that might cover nooks and crannies, not all of the exposed surface will normally be covered. And so a 'two-toned' treatment is worthwhile, where most of the surface is more or less 'clean' steel.
I make these comments after observing such matting installed at DEW Line hangars in the Arctic, with samples both inside on hangar floors and lying about outside for 30 years.