I think they look like pigs just from the form you made, I think that the less detail the better. You could try putting a curly tail on them in satin stitch of same value of thread, and then consider cutting, fusing and stitching on a small inner ear. A single stitch around the nose profile, perhaps a little stitching on the hooves just to ground them. I just finished a baby quilt of appliques, and there wasnt so much stitching as cut out pieces appliqued on top and then stitched. You are correct, it is hard to control satin stitch, and I found that if you are trying to use it to hold the applique in place, it is usually too much and too heavy.:)