great modern quilt! I'd probably do each block with a variety of straight lines and wavy ones--maybe one block divided with lines going vertical on one side and horizonal on other side; or starting about 1/4-1/2" from edge of block and then creating a concentric box, etc. One block with wavey lines going one direction, another box with them going the other direction. Check out Angela Walter's website, "Quilting is My Therapy" for some ideas. They tend to be very straightforward and don't really need to be FMQ.