I have always been taught that there are really only two considerations necessary when determining the amount of quilting needed on a quilt. Both have been mentioned, but I would like to mention them again. The first thing that is most important, is the amount of quilting that is recommended by the batting used. That is why I like Warm and Natural. It can be quilted 8-10" apart. Some of the other batting requires quilting at 2-4". Otherwise they will not hold up to washings. Whatever amount of quilting you choose to do, it should be evenly balanced throughout the quilt. If you use heavy quilting in one area, all the other areas should be heavily stitched. If you choose to go easy on quilting, go easy over the whole quilt. Especially if it is for a wall hanging. If it is not equally quilted it tends not to hang well. I personally like to SID to stabilize the quilt, but then add a small amount of free motion quilting in the blocks and borders. If I appplique, I outline the applique. I also love to do vines as they are easiest for me and are very forgiving.