When you finish this, they'll love it. How big is it, and how much larger would you like it to be? I'd narrow that wide outside border to 4.5 to 5 inches. Add a narrow white border (or black), about 2 - 2.5" then the piano key idea is wonderful. Make it up to 6" wide, using all the colors in the quilt. Bind in black. Enjoy, it's great so far.