That's a good size quilt, must have been hard work quilting by machine.
Is the flying geese border the same as the 6" border?
I think it depends on the batting how much quilting it needs but 6" is a big space unless there are other ditches. My choice would be to use the same amount of quilting as in the main part of the quilt. It'll look balanced and be a better shape.
Can we see it pretty please