No rules! It sounds like you have a good idea of how you'd like it to look, you just need to decide on a technique. Space between quilting is limited by the batting. Some batting will allow you to space stitching further apart. Do you think some of the big stitch hand quilting would look good? I don't think I could FMQ something that large on my domestic machine. If you're going to hand quilt, you might pick a batting that is recommended as easy to hand quilt.