I agree on the essential. That said Bladetips Energy blades seem to have a low aspect ratio (see below) and a relatively high area, likely in order to assure lift by active pitch control. And also the turbines are not settled in the tips of the blades. So they don’t benefit from the maximum linear speed, and should be larger and heavier to compensate this. See also Blade Tip Turbines topic.
It is the reason why I would prefer blades with higher aspect ratio for a better efficiency, and turbines settled in their respective tips. I put again a photo from quoted topic above. This rotor would be used under a kite lifter as for the drawing in the initial post. Perhaps I could remake it then test, at least its TSR with then without turbines.
