I think I'd pick out a matching solid color (the red or the green) for the runner, then edge it in the plaid (or put a plad strip in the middle).

I agree with pbrijar. You did a nice job on the curtains.

Great idea pbrisjar has! A solid with your pretty plaid as a border would be a nice touch. Excellent job on the valance! It looks great!

Or you can do a reversible table runner with the plaid in one side and say gold on the other side.

Great ideas! Thanks. I'll go ahead and buy the extra fabric and that way I'll have the freedom to be creative. I could combine threegrad's idea with pbrisjar's and have it plaid on one side and a solid bordered in plaid on the other.

Or solid center with plaid border on one side and plaid center with solid border on other side.

Here's a runner I made with contrast inserts. This allowed me to use leftovers from the draperies and "play up" the seams. I used the same contrast fabric for piping the perimeter.

Here is a link that might be useful:

I like Threegrad's idea.

BTW, your curtain turned out great! I love the way a plaid looks with that treatment.