hey there Tom, wondered what your topic was about, looks like a nice dio!
some pointers (if I may)
layout is great, nice to differ from the straight edged set up's
won't be going into the vehicles not the scale, as modern allied and choppers aren't my strongpoint
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the drums could use some aly chippin on the ribs
a wash with a sand yellow pigment would do nice on the vehicles
and the bushes, try finding some weeds ,fine flowers,let'm dry, see what is usable in your scale,then paint them ,be gently they are fragile, and it will look much better on you dio.
some very fine ground up yellow artistic chalks,sprinkled on a bit of white glue or acryl resin, will look like dust piles once dry,try it on a piece of waste,it's cheap
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greetz Tha Pit