I debated quilting more heavily in the stars but I really wanted them to be floating in front of the spirals. When I quilted too much in the stars they receded to the same layer as the background, so I decided to mostly stitch in the ditch, with just a bit of outline quilting.
For the borders I finally decided to quilt sets of 60 degree lines in the corners and join the corners with plain straight lines. Once that was done I thought the plain straight lines looked a little stark, so I stitched a few sets of 60 lines randomly through them. That broke up the border nicely and echoed the straight lines in the quilt. I had trouble getting the full effect to show up in the photos though. They look more effective as a whole than in bits. You can see a bit of it in the next picture.
UPDATE: The pattern is now available! Whoop whoop!