Her approach was defined by a preference for texture and material over literal representation. In her portraiture, such as the painting of Martin Brimmer, she used a restrained palette to focus on the character of the subject. This same discipline appeared in her stained glass work, where she utilised opalescent glass and irregular shards to manipulate light. She avoided the industrial perfection of machine-made materials; instead, she chose hand-cut pieces that retained small imperfections to create a sense of movement.

Modern collectors value Whitman for her ability to bridge the gap between fine art and functional design. Her work possesses a graphic quality that feels contemporary despite its nineteenth-century origins. The clean lines of her book designs and the balanced colour fields of her portraits suit modern interior spaces. Her pieces offer a connection to the intellectual circles of old Boston while maintaining a visual simplicity that remains relevant today.