All very good input. It is true you will end up with several set of lines. Not just different strengths, but also different lengths. As to you putting a knot in the line. A knot will reduce the strength by 50%. Sleeving a line is not a hard thing to do. Another option for line choice is “Power Pro super 8 slick” fishing line. I fly 80 LB on a lot of my kites. Have never had any problems with it. It's braided, light weight and cheaper then regular kite line, plus you can get it in different colors depending on where you are flying beach, grass.