Do you know her decorating style? Those colors suggest simple and modern, but I would ask her to describe her tastes or show you photos of decor pieces she’s drawn to. Example: big prints, small prints? Geometric or solid? Dots or not? Stripes, chevrons, paisley—yay or nay?
My 2 daughters-in-law and daughter all use grey as their neutral, but one house is “coastal “, one is modern urban, and one is vintage themed. I love them all, but those 3 sweet girls are all picky so I would rather have have their input on something as enduring as a quilt.