I improved (in my opinion, anyway) upon my previous design. This time incorporating the X into the knotwork. Also I made the ropes a little thicker so the knotwork is tighter. (I have a lot of time at work where I have no classes, and thus nothing in particular to do.)

Please see "Version B" in my personal photo gallery.

It would still need some fine-tuning to make it more symmetrical, but I think it would make a good looking pin.