I'd use both. Try my lazy method, which isn't a long strip for a border, but lots of border blocks. Do a thin strip of one of your border choices to go next to the block, the same width as the small square next to the blue star points, then a broad strip of the other colour the same width as the bigger square which is next to the red star points, then a thin strip of the background colour, then bind it with red. To make it more interesting alternate the blue and plaid on the border blocks, so the first one is blue, plaid, background, the second one is plaid, blue background etc etc.