Re developing a standing wave with the fly line, I've seen a standing wave with one of my kites and the line leading to the drogue behind it. In fact, I've read that the tow line for a drogue should me a non-integer multiple of the length of the kite (e.g. not 2x or 3x the length) to avoid this phenomenon. There's a great old black and white newsreel of a bridge falling down because of a standing wave amplifying the force of the wind. You know you're a master flyer when you can look at the kite and line and say, "I think that's a G sharp set up".
How close are you to Treasure Island? The Kiting Tampa Bay Club meets on the third Saturday of each month behind the Thunderbird Hotel. There you will meet single, dual, as well as quad line flyers that can help you along. It's a good group of people, & a great beach to fly on. Go & have fun.