Wow, that quilt definitely talks, what a great pattern and beautiful piecing!
I know you're not liking the idea of quilting on the prints, but I'm seeing quarter circles (similar to a baptist fan pattern) in the printed circles, stippling (maybe small cherry blossoms) in the white square areas to make the black squares and prints pop, and leave the sashing strips alone.
No matter what you decide, this is a stunning quilt and your friend will be ecstatic!