Schleich used a disciplined line to create depth. His approach favoured clarity and structural integrity over soft shadows. In portraits of figures like Molière or Pope Pius IX, he focused on the anatomical accuracy of the face. The use of steel allowed for a higher number of prints without losing the sharp edges of the original design. This method ensured that every print maintained the same level of detail as the first impression.

Modern collectors value Schleich for his technical precision and his connection to classical literature. His work provides a bridge between the written word and the visual arts. These engravings suit contemporary interiors that favour monochrome palettes and historical subject matter. The sharp lines of his "Ecce Homo" or "Death of Ballyn" offer a sophisticated aesthetic for minimalist or traditional decor.