I have always had the best of luck creating embroidery on leather. Recently, my client Randy Patton of Patton Design Studio asked if I could provide embroidery on suede for the inside chair back of a National Upholstering Co. lounge chair. The project is in Colorado and the home is associated with a brand. The above represents the brand with the outer portion being a stylized horse shoe.
The thread coverage on this project is pretty high as I chose to run underlay to secure the leather on the frame and to stabilize it from stretching. The final result is 8" high by 7.25" wide and is just under 38,000 stitches. The photograph of the panel on the frame shows the underlay sewn in the first phase of the embroidery process.
Leather is also nice for Trapunto - however, a think leather is best for this process as the relief from the fiber fill is greater with thin surface leather. Kidd leather and pigsuede work nicely.