While I understand what you were going for with the silhouette framing the scene, it seems a bit boring visually because the silhouette doesn’t really add anything to the scene, other than take up precious real estate that could have been used to make the scene more compelling. When you use silhouettes, you have to think about why you’re doing it. The addition of the silhouette have to have meaning–a specific purpose that was made more effective/powerful by the silhouette.
Some of the stuff in the far background is a bit too vague. For example, on the right side, those two white vertical streaks–are they supposed to be waterfalls? We can’t tell what they are. You need to make sure everything in your scene reads clearly, even if they are meant to be far away and with atmospheric perspective.
The way you have depicted the forms with highlight and form shadows seems a bit inconsistent too, as if the position of the sun keeps changing in the sky from one column to the next.
The perspective also doesn’t line up. Your waterfalls should follow the same vanishing point as the building.