I really like the system shown on that Mystere 6.0 picture you posted. The wings stay put and can fold up easily for trailering. As an added measure of safety, you could run a third "trapeze" line from the mast to the middle of the wing for support.

One of the drawbacks to wings is having the leeward side hit waves or drive into the water if you fly a hull too high. I hear tale of an open Worrell boat that had wings that were supported by cables from the mast such that when one would go down (if the sailors sat on it) the other would raise up to 90 degrees or so.