Your quilt is stunning and counted crosstitch too. I am so impressed.
I am not a veteran quilter but I made some quilts for my grandchildren and in the center block I painted Precious Moments pictures. When machine quilting I did the "echo" around the pictures and wherever possible, i.e. the sleeves, apron etc, I quilted in the picture. Just do enough to hold your batting and enhance the picture (what you want to puff out). I would do a sample first before tackling the whole project it is so beautiful.