Hey Dun-King,
If you are mega overpowered and are being tea bagged towards obstacles, you should either let go of the bar and deploy the safety system or just purposely crash the kite into the water and that will stop the carnage. if you are in clear water, point the kite out to sea rather than at the land, it's always safer in the water than terra firma.
As for line length, you are correct.
Good winds,