Getting back to the original topic... Sounds like those in Canada push their cars to the limits with the long distances they need to travel and the cold weather..
I agree that the OP's complaints are not the function of the car being a problem. The electric car is not an equivalent to the gasoline car. Gas cars are much more powerful than in the past, and we think nothing of pushing the speed to 70, 80, and more.
The EV, however is subject to the limits of wind resistance, which is a geometric function, with the car needing increasingly more energy to move the car every mile per hour more than a certain amount.
The OP should try to accept that he DOES NOT HAVE TO TRAVEL At 75 MILES PER HOUR with an EV. Let the traffic respect your wish to travel the speed that you want..... You will get much better results at 55-60 MPH, and running the heat at a constant, modest amount. The Leaf will not yield to your will, you must yield to the laws of physics. As I understand it, wind resistance increases with the X (squared), where X is speed.... So compared to a 50 mph car, at 60 MPH, the resistance is 150%, at 70, the resistance is 196%, and at 80 it is 256% of that needed at 50 MPH..