After World War II, Sims returned to illustration and painting and created a number of somewhat surreal and meticulous, finely-detailed gouaches. There are approximately 30 images of this kind. The variety of subjects include stylized figures in elaborate costumes, ballet dancers, circus performers and botanical studies.

During the 50s and 60s Sims was also painting large scale realistic imagery in watercolor of figures, portraits, still-lifes and landscapes. Only a few of these works survive.