Thanks, everyone, for the suggestions!
I had thought of straight lines in the center section. But now the thought of the straight stitching in the red border sounds interesting. I'm not sure I can pull off the shadow outline, though I think that sounds lovely!
nativetexan, I can't picture the zigzagging...I may be too tired! After dinner, I'm going to try to sketch out what you described.
No decorative stitches (just zigzag type stuff)
Thanks again!