On a visual level, Darkman goes for the fantastic. Westlake wears dirtied bandages and a long, flowing trench-coat with an antiquated cut. He makes his home in an abandoned factory filled with pipes of all sizes, a huge fire pit and later a room filled with the assorted masks he has built. The climax takes place in the framework of an under construction skyscraper, complete with other partially finished towers surrounding it, all of them sharp, angular and glassy.
It is a distinctive look that provides further contrast between the patched together Westlake and his perpetually suave, in control enemy. While most modern superhero films work to make the setting as grounded as possible to contrast their fantastic characters, Darkman and its contemporaries used their settings to highlight the fantastic aspects of theirs.
While my own personal taste in superhero films runs more toward the modern, dismissing Darkman, or any superhero film from that generation simply due to its age and vastly different style of filmmaking would be a mistake. They are a vastly different interpretation of the superheroic concept than is currently popular, and for the right audience, perhaps a more appealing one.
Each generation of superhero films, and for that matter, film in general, has something to offer. In this specific case, it is a much darker tone, a more intimate look at the mindscape of a few characters and fabulous, marvelously impossible settings.