If GRAN picked them out...I'd use them only...its her quilt and her choice of fabrics...that in itself will be beautiful to her not mentioning the fact that YOU made it for her..I think ALL the fabrics are lovely and will make a beautiful quilt...I think you will be more pleased using her selections
I wish my grandmother was alive so that I could make her a quilt...but she has been gone 32 yrs now. :-(