I posted this article, so obviously I mostly agree with it. But...
It says the MIT study found that a car with 73 mile range could cover 87% of all driving days. But to cover 73 miles, you might need something like 120 mile range in the middle of winter and freeway driving. If a car loses 10% capacity by 100k miles, you may need 135.
It's always a little scary to pull in to your driveway with 5%, so you need a little cushion on top too.
I think having 150ish miles is probably a good target.
Look at the big brain on macrocephalic