In the old days, (using film) To get lightning shots I would just open up the shutter and leave it open until a couple flashes of lightning hit. That was the easiest way at night to get lightning shots. It would be nice if there was a "bulb" setting on the drones to create some artistic night shots. The longest shutter speed shot I did was 8 seconds on an X-Star premium. You can see some of the taillight steaks on the right side. It would still be nice to be able to hold open the shutter manually even though movement of the drone would eventually cause issues.
Great shot by the way, those are tough to get from a drone!