Dennis,

If you go with the seperate tack line like in your second sketch run the tack line through the back carabiner and then to the second one and get rid of the shock cord. When you pull the tack line on (kite up) this will give you slack in the halyard/retreval line. Then as you douse the kite and the tack line runs forward it will suck up the slack and everything will be nice and tidy. If you then run a retreval point to the clew as discussed in the f16 forums at length (do a search) you'll end up with a nice tidy tramp upwind.