What fusible did you use? That answer may very well have a bearing on whether stitching is required. I frequently leave raw edge appliqué pieces unstitched and have never had anything fall off (or even loosen up) over time (going on 20 years for some wall quilts). The key lies in making sure the bond is solid to begin with, neither over nor under fused, and the work remains flat even if/when stored. Batiks hold the bond especially well because of their higher thread count. Nice work!