I would say that this dramatic and beautiful quilt only needs a border if you want it bigger. IMHO, a black border or a very narrow red border followed by a black border would not detract, however. My teacher would have said to put it on a flat surface with a long piece of fabric the size you are considering peeking out from under it. Ultimately, it's your quilt, your call and you have been doing just fine so far. Trust yourself.