IMO I would not change the quilt. It was gracious of you to finish it for her. She did not say anything about size. Apparently her daughter does not understand the difference between a massed produced bedspread and a quilt that is a work of (he)art.
Personally, I would be thrilled to receive a quilt made from blocks my grandmother made and pieced by a dear friend of my mother's.
The most I would do is offer to put a sleeve on the back so she could hang it.