Well, I don't know about changing the color of the finish on upholstery leather. Someone else may know more about that, and I wouldn't mind knowing a good answer to that question, myself.
But my thought is, maybe you can make the pieces you make with it more attractive by adding some ornamental hardware, such as conchos, decorative rivets, some bling-bling (which by the way, is not really my bag, but a lot of people like it), or beads.
Another possibility is to add some trim pieces made of tooled veg-tan, or perhaps even some leather appliques, ala Peter Main.
Kate