Both images really take different approaches to composition. The image that is of the brick wall is much more angular than the image of the skyline. Seeing these images side by side is great because it really showcases the difference that angular perspective has.
Don’t get me wrong, your city line photograph is not flat in a boring way, it’s just flat in the way it approaches the composition of your subjects. The buildings are straight, with strong horizontal and vertical lines. Your other image however uses many more diagonal lines which help not only guide your viewer’s eyes into the photograph (great leading line by the way), but also help provide the image with a much more angled feel.
That being said, both images accomplish exactly what was asked from you for this assignment. They are both brave, wide shots with strong compositional strengths.
My main concern has to do with the tree in the cityscape. Notice how the left wall of the frame cuts 1/3 of the tree off? As a viewer I find that looks unintentional. I obviously don’t know what would have happened if you included the entire tree (i.e. maybe you would have been forced to amputate a building), but generally try to include all of the object when it’s acting as one of your primary objects.
Other than that, I think this is a great shot! Keep up the great work.