I think your open areas are a bit wide open. That being said, if they are less that 4 inches, you should be covered. Any thing MORE than 4 inches needs more quilting. I just doodled a bit (and luckily for my customers, I'm a MUCH better quilter than artist!)..how about something over the intersection of the blocks? The circles and arcs would be a bit harder. but a Diamond is straight and you could use a walking foot.