MacThayer

I have an alternative. Start with the first inner border you have as is, with the red and the diamond shapes, then add a different border, again with the diamond shapes, maybe widening the borders a tad. You could continue to use the red, or you could see what a different color might look like in between. Or perhaps make the first narrower border something other than red (but not green. I preferred the black) and red for the two wider borders. These are not the right colors, but here's a pattern and a sample.
I'd almost like to say "rotate the position of the diamond" just for a bit of contrast, but that's a bit dicy! Perhaps you can do it with the direction of the pattern in the fabric? Maybe someone else has a better suggestion.