Beautiful quilt top you rescued!
I'm trying to remember the quilting on the one I slept under for years. I know the white areas were echo quilted 1/4" from the seam with an X in the "football" and cross-hatching on the larger white area. The squares were also done with an X. What I don't remember is the quilting on the arcs. It may have been stitched in the ditch creating a vertical pattern on the back or else parallel lines following the curve of the arc in a more horizontal or circular design. Very simply done, no fancy designs.