I agree with everyone.... the star itself is GORGEOUS. Take the floral border off (be sure to save it... there is no trash when it comes to fabric). I do differ in that I don't think a dark color will ground it. Try a blue, aqua/green or rose/pink that is in the quilt, but nothing splashy that would draw the eye away from the beautiful star. Try to stay in that color depth.
Nice job .... stop being so hard on yourself. Be sure to let us know what you have decided. :)