On the first quilt, “I” would bind it in the background fabric. The dark fabric (I think) will detract from the center of the piece by bringing the eye to the outer edges. You want the center motif to stand out. By using the background the center motif will be the focal piece.
I must add Marian, this quilt is beautiful. you have come a long long way in a very short time. I hope you do well in the competitive show you plan to enter this in.