I am looking forward to see your sketches; (to see whether I am getting an accurate picture of the concept you are proposing).

Good British humor, that ... (your statement that) "one WIG needs about 250 HP to move six people at 80 knots". We can discuss that at another time.

For the purposes of this discussion, let's remove 'ground-effect' from the equation altogether for the moment. Let's also remove 'keys' from the equation.

The visualization of your concept which immediately popped into my head was (and please correct if this is not what you intended) ... a manned vessel - (which replaces the keys). The vessel would be towed by the kite (which would act like a power-source much like in the Jellyfish Foiler concept); and the 'parachute' would be like a proa sail (or similar to the aerofoil incorporated into the Monofoil) which would not only provide power at the lower level, but also 'certain control functions' for the vessel at the lower level.

IF the above is what you implied, I think you are talking about a concept which goes far beyond my original speculations. You are not only talking about raising the craft free from the water surface simply from a water speed perspective - (to obtain freedom from the drag of the water surface); it seems to me that you have proposed a true 'Flying Dutchman' - a sailing craft which is capable of travelling at great heights above the water surface. Manned control of such a craft would be 'difficult' (but not impossible)and as Johan pointed out the craft would have to be very large scale to be manned ... (wouldn't it?).

I was intrigued by Johans' mention of the 'daggerboard' concept. Although 'cheating in a sense'; (you are still dragging something in the water), it could provide some lateral stability while lessening the 'drag' from other concepts tried.

Looking forward to further input.

Cheers

Foxx