Since electric drive is inefficient on the highway, but more efficient in the city, I would like to have a user-defined speed where the engine comes on automatically. I would have an 'Auto-On' option in settings that turns the engine on at 50 mph. Others can change it as they wish. Yes, it's easy to turn on, but my wife hates cars and she hates even more cars with many buttons. For her sake and all the people that shifting into 'D' is the max they are willing to do, please automate the driving efficiency as well.