Isn't cruising power much lower than takeoff power? Having enough batteries for takeoff would make these number much smaller. A lower cruise speed would also

Isn't cruising power much lower than takeoff power? Having enough batteries for takeoff would make these number much smaller. A lower cruise speed would also decrese these numbers. There is a point in the efficiency curve when it increases the total energy used, but still decreases the power. Maybe it's not a big difference, but using the takeoff power seems unnecessarily pessimistic.