I somewhat agree with sewbizgirl. Treat this as a panel. Maybe even downsize it to what you want in the center and put a small border in, then repeat the focus fabric as an outside border. Another idea would be to leave it as is and use your fat quarters as a piano key border.
Depending on how big those designs are, it would be easy to quilt a curving line around the "medallions", letting them be showcased. Mostly a "rule of thumb" is to have quilting no more than 4" apart so I'm not sure if this piece meets that criteria. I'd do quilting that highlights this design since you like it so well. Many of the other alternatives could override the very thing you like about this piece of fabric.