I think the border disappears next to your blocks. I would suggest a flange or narrow border in black to stand up to the design, then add two borders, 1st 3", 2nd 5". I think a strong light inner and maroon outer with same color binding beyond the initial flange.
Just my opinion - love your fabrics. I HATE TO RUN OUT but sometimes things work out even better that way!!
Thank you so much, I can look at others quilts and be more objective than with my own and alway ask for advise.