A South African kiting wizard (the cool bloke with the cowboy hat who was at the Skem kite festival some weeks back) told me how to make a cheap DIY kite strap as an alternative to a harness. It goes around your waist and attaches to those two loops on your handles (where you peg them into the ground). I made one recently from two shoulder straps from computer cases. You know the ones? ...black webbing...with two hooks or clips on the end?
Anyway, it works fine and its a bit of fun now and then ...but I dont use it in serious winds ..just in case
By the way, the advice I received for ejecting from the home-made 'back-strap' - is to duck forward and push your hands and arms out in front of you - and (in theory) the strap rides up your backbone and over your head, without taking your ears off!!