The tank and figures are nicely modelled. I like it a lot, even though armour (especially German armour) isn't my thing. That said, I've always had a soft spot for the Panzer III & IV.
Unfortunately, the rocks don't look at all realistic. They look like painted blobs of plaster, though I like the way you have blended colours & shades and used drybrushing. If you can add some more realistic structure to the rocks, then paint them the same way, they'll look much better. I have to admit though, that others may not notice this point; I am a geologist, so it caught my eye immediately.
Lastly, I'd recommend that the rollers on the tank look more dusty. The scene suggests a very dry, dusty setting, yet the tracks rollers look like they've just been through a car wash.