One of my favourite uses for the 9 Patch is to set it with an alternate block, this has the effect of creating a frame around your alt bloc, either diagonally or horozontally, depending on how you set your blocks. You can use another pieced block as your alt block or some applique. Or you can use that lovely blank space to feature some fancy quilting
On point set gives a horozontal frame
[ATTACH=CONFIG]24870[/ATTACH]
9 Patch set with applique heart block
[ATTACH=CONFIG]36641[/ATTACH]
Straight set gives a diagonal frame
[ATTACH=CONFIG]63000[/ATTACH]