Another way to think of it is that the borders get the most wear in use. Think about it; you virtually always use the borders when moving a quilt, so they get heavy use. You need to "strengthen" the borders with some kind of quilting so it will stand up to use. But you don't have to pick a style that is difficult for you to do! Straight lines or stippling will work just fine, and they won't compete visually with the the quilting on the rest of the quilt.