Gday Brad
I'm out on a wing and a prayer here, as I know next nothing about modern stuff, so I'll comment on the groundwork...
The basic layout is good, and composition-wise it works for the fact the tank is at a good angle to the stone wall (Which looks bloody effective by the way!) Essentially you would not want the main feature of the groundwork (ie. the wall) running parallel to the base's edge though...
The grass tufts are good but can be improved by a bit of randomness. Throw some smaller length tufts near or next to the existing, and some scattered stones in and under them...
The aerial shot shows how uniform the placement of the figures is. Maybe break up this pattern a little?
But wow you have captured an arid region well here!
And for your first, I tilt my cap to you
Cheers
Brad
P.S. Good name too :-)