His artistic approach relied on pen and brown ink combined with delicate watercolour washes. Nicolle was a master of the veduta, or view painting, focusing on the structural details of buildings and public spaces. In works such as Villa d'Este and Behind the Palazzo Barberini, he used light and shadow to define form. He frequently added small figures to his compositions. These figures provide a sense of scale and depict the daily routines of the local population.

Modern collectors appreciate the technical precision and clean lines of his work. His drawings, such as Scene Along the Grand Canal and Antique Interior, offer a historical perspective through a graphic style. The use of neutral tones and washes makes these prints suitable for contemporary rooms. They provide a view of the past that is observational and grounded in reality. The small scale of his original works translates well into prints for the home.