~Bill~ I'm happy you feel I helped, and it's nice you seem to appeciate it it, but I don't see that you accomplished(even with your limited timeframe)what I was trying to relay, or what would look best / give some 'pop' to that base. You got it grunged-up a little more than the first attempt, but you didn't end-up with hardly any contrast between stones & gaps.Now, it's not the worst thing ever, but it could be way better, without much trouble. I think what happened is you have it your mind that a wash should be subtle, heavily diluted,ect. Not so with groundwork. The ground is a harsh place, and a stark contrast would make the base 'pop'. Every artistic persuit is a study in contrast & consistancy. Every one. Your base has too much consistancy. In the pix at the top you can see me laying in a (Heavy) dark wash(you could even say filter)of very dark grey-black, which also gave varriation to the stones.(Vespa's advice was great too, the stones need to appear to have varriation, and you showed promise painting them at least 2 colors)
But then I think you went too light with whatever your wash mixture(s) was. The dirt mixture I showed was heavy & wet(the alcohol running inbetween the cobbles and carrying alot of color - but evaporating quickly)
A totaly different method, if you like, take some near black(grey,brown)Enamel, paint the ENTIRE thing down, then ball-up a rag and buff it over the stones,wiping near-all the paint off then, but leaving it in the cracks. Let it dry an hour or 2, and hit it with some Dull-coat.
~ Also, are you going to apply some stain to the wood plinth? I would. Or do want a natural wood look. Just a matter of taste,but it touches on composition too, do you really need that contrast- between one part of the small base and another?
~Still tryin' to help..............Indy