On the whole I like it....you've got a good eye for 'dramatic'....
You've obviously paid attention to the technical side of this....the shadow of the rock on the right on the clouds is just about spot on.....nice.
There are though just two things that bug me.....the central 'building' and the darkness.
First the darkness: Although dramatic its just a bit too dark to really appreciate all the work you've put into it. The detail in the rocks and buildings is just lost.
The second thing is that central building.....would the front really be lit by the sun?
Its obvious that this building isn't very far away from the 'viewer'. Its also obvious that the sun is considerably further away from the viewer. For the front of that building to be lit, the sun would need to be nearer to the viewer than the building itself. You've got the left hand building spot on so....??
I can see that you have a shadow on the wall from the window but I'd say that the whole wall would really be in shadow.....especially when you look at the rock it sits on....the face nearest the viewer is in shadow....stands to reason the wall would be too.
Apart from those minor things its a great piece.
Regards.
MrToM.