I think applique flowers would be a wonderful addition to help that wide solid border not look so much like an afterthought or something added to get the quilt up to a particular size. You definitely have some very nice colors in your focus fabric that you can bring out in the applique. You can pick up the pink you used in the inner border and also the soft green that is in the fabric for the vines and leaves. Another consideration is using some of the more colorful hexi's to suggest a flower. If you have any left over. I definitely see a couple of hexis that look like a big flower. It would be a neat addition.