This FMQ design makes a great sky. It's basically Leah days posiendens eye design with some McTavishing thrown in. The swirls look better with the middle a closed circle, which is what you're supposed to do with posiedens eye (as in the swirl top left). As you can see my quilting on this one is far from perfect but it still works. This is very forgiving - who's to say which way the wind is blowing or how?
Try it on your next sky :-)