His approach to composition often involved unconventional lighting and elongated figures. In works like Petrus geneest de verlamde man in de tempel, he uses complex architectural settings to frame his subjects. He favoured a style that leaned towards Mannerism, where the human form is stretched and placed in dramatic poses. The use of shadow and light creates a sense of theatre that differs from the more literal interpretations of his peers. He often drew from the fantastic elements seen in the works of Hieronymus Bosch but applied them to religious scenes.

Modern collectors value Aertgen for his idiosyncratic perspective and architectural precision. His prints and paintings offer a window into the transition between late Gothic styles and the emerging Mannerist movement. The way he handles space and scale makes his work suitable for contemporary interiors that appreciate structural geometry. His art provides a historical depth that avoids common clichés. It remains a choice for those who prefer the intellectual rigour of the Dutch masters over more decorative alternatives.