Scan the picture into a program so you can repeat it over and over to see how the entire quilt will look. You can show that to your sister to give her the chance to see if it will be too busy when it's Huge.
If she still loves it...feel honored that she treasures your ability and skills to make something so nice for her. Put her picture next to your machine and say over and over, I love you Sis...I really do Love you.
Since it's being made with love, it has a beauty beyond compare.
BTW...I really think it's cool.