I wrote a thesis ten years ago which examined the engineering and economics of a more simple kite/glider pair system. Aerodynamically, it can be stable and self-correcting, which I modelled and prototyped, but this may not be an optimal design and launching is hard due to lower (and different direction) ground wind and boundary layer issues.

The drone-like addition adds control complexity, but appears to ease take-off and can probably reduce strain in flight and improve efficiency, despite the aerodynamic cost.

Tower wind turbines have enormous costs and engineering trade-offs: the generator is in the nacelle up high, adding structural cost to the tower, which, at 150m+ nowadays, is a big deal; not to mention the rotors which span the area of a sports stadium. This doesn't scale, whereas kites do, because the tower/blade height/length cost is gone, the generator sits on the ground, and can be bigger (easy access, cheaper, heavier magnets, among other benefits).

Maintenance (and finance of turbine project bearing this in mind) is huge. Servicing an offshore turbine is weather limited and expensive even if you can get there. For kites, just reel them in by pulling more power off the generator to wind in the kites. If they are offshore, then sail the boat (?autonomously) back to a harbor. The list goes on and on, and amazing possibilities open up with a moment's thought.

Agreed with responder that it is early days for the technology, but I expect strong progress through up learning curve from this early stage. Good luck Makani!