This personal project was inspired largely by a painting by William Parrot - Views of the Hotel Cluny. It is not an exact recreation but retains most visual elements that painting has, such as the cylindrical part of the center building, and the trees on the courtyard. I could also find no credible source if the painting were actually his, as there exists very little information about his life.
I agree, the pot in the front and the pillars and walls on the left could definitely have used some. I did add what I thought was quite a bit of grunge on the towers and central building, but i guess they just were not as visible when rendered.