Wow, the quilt is fantastic. You must be very proud!
I think a box pleated bedskirt trimmed with the border fabric would look fantastic. Here's a link to a freebie pattern:
http://www.ehow.com/how_4928925_sew-...-bedskirt.html
Also have you ever seen those curly little pins for anchoring bedskirts?
http://www.beddingtons.com/p-2267-bedskirt-pins.aspx
You could create your whole bedskirt as a long length of fabric and pin to your own specifications without putting a full piece on the boxspring.