Where do you live ?
For those monthly 300 to 500 mile trips I can rent a car from Enterprise for $14/day. Even if I pick it late the worst is $25/day.
I would sure rather pay $25/day 12 times a year and only spend $800 a year on the electrical costs of a Leaf ( EPA estimate ) the rest of the year.
Find an online interest calculator and pretend to invest the savings from an electric car compared to an average gas car for 20 years; it can be the cost of a college tuition or 1/2 the price of my house when it was new. Don't forget that money spent is after tax - you really had to earn more then what you spent.
Now don't electric car(s) deserve a second look ?