I think also that probably the easiest way to do this would be to integrate beads into the tether that these clamps then clamp onto.
Given this, you could then also connect these beads to a conductive cable inside the tether. And then connect the conductive cable to a slip ring between drum and shaft, and you’d add another slip ring between shaft and nacelle. You’d only send (max) power through the cable once the tether was completely unwound from the drum to avoid the cable heating up too much.
One imagines it might be a good idea anyway to add this even if you don’t go for flygen to power things that need power on the kites.
If you do go for a flygen system, and since now you would have lots of generators in the air, you could connect them together in series and with that increase the voltage and with that make the cable much lighter, I think that’s how that works: Lightweight conductive tethers, fairings around tethers since the cable is airborne and not in danger of being touched, I think it also makes sense if the need for cable insulation decreases.
And since with flygen, or yoyo systems, if talking about a system like the Pyramid, you don’t need torque transfer after the launch, you could cinch together the tethers from the different kite trains to reduce tether drag, or fold the arms up, like a flower closing up.
I think none of these options rule out using a lifter kite train or things like that, at least for initial development so your kites won’t crash as much then.
I also think flygen would probably be easiest to develop, but torque transfer perhaps more viable, if it works.
What do you think?