It's good that this is becoming possible, but what I'm wondering is if it will open new possibilities. Electric engines are more versatile than gas ones; for instance it's not a problem at all to cut the engine and restart it later. Could this enable hybrid plane-gliders that would glide as much as possible, and only restart the engine when needed?
One thing that has struck me is how remote-controlled drones are almost always quadcopters, instead of looking like regular helicopters. If you take away some constraints, suddenly you have a lot more possibilities and you find different solutions. I hope that electric planes could bring some fresh designs.