bearisgray

Each unit seems to draw out on a 4 x 4 grid.

If I was making it, I would make 12 inch (finished size) blocks - the diagonal of a 12 inch block is approximately 17 inches - set them on point -

I would leave each large square as a large square - enough triangles with the flying geese units -

I would construct the corner units - then decide how much of a filler strip is needed to make it look okay to my eyes.

As far as I could tell (measuring the units on my computer screen) the border flying geese seem to be the same size as the flying geese in the body of the quilt.