All very interesting but the upwind component is just not worthwhile. The vari-trac gizmo is just there to change the kites attitude to the hull, not for tacking. The more the ship is sailing downwind, the closer to the bow the kite is sheeted. Closer to the wind, the kite is sheeted aft.
The kite will not tack. It will collapse. Even if it could tack, it would now have the normal trailing edge (leech) as the new leading edge (luff). It is not a symmetrical foil.
50° to the wind is nothing to write home about. In practice it would be a bear to try to sheet in every puff, lull and oscillation and I would imagine that steering a wide, heavy ship up and down the apparent wind angle would be out of the question.
This thing could have some practical applications but time is still money in the shipping business and wandering all over the ocean will not be popular with shipping agents, port authorities who are expecting your arrival or customers.
The fact that this is (partially) filled with helium (patially) solves the the problem with luff.
That said, I think sticking wings of old DC-10s on the deck with some clever software and adding an adjustible keel would be a better solution.
There are also metal rotating cylinders that can be placed together that work well --- this was the big idea just as steam came along and replaced sails, as you could tack just shy of directly into the wind. Just a few years ago, I saw lots of small boats in the Phillipeans (sp?!) with things that looked for all the world like twin toilet paper rolls spinning where a mast would be --- apparently very useful in shifting wind currents and easy to maintain.