Unless you need it a certain size, I vote for no borders & yarn tied. Looks so cozy! If you need a border, I'd go with either that deep blue-violet in the middle or the muted dusty green in top right corner. Saturated red is such a strong color that if you add even more with a border, the other colors will get overpowered & lost; it will end up just looking like a "red" quilt. Not a problem if that's your goal but I think pulling out another color in the quilt will help the red to shine & bring out some of the other colors as well.