You’re really setting an expectation for your range to be 1/3 of advertised range in the winter? The Lightning will be my first EV. I fully expect a range hit in the winter as well, but was sort of still anticipating 200+ in winter, not 100. HmmmI am setting my expectations conservatively to avoid disappointment. If I can get 100 miles in the winter on the ER battery, without pre-conditioning, I will be happy (Wife's Mach-e will be plugged in most nights - she has a longer commute).
As for a heater - it is effectively certain that some kind of battery heater will be there. I think the only question is if it is resistive, a heat pump, or some combination.