I had 6 cellar windows repaired by people recommended by Jade and they came out great. I'm not much of a handyperson so I deal with contrators to get things done.
I then had storm windows put on by a company recommended by the window restorers. You might not approve of them but they protect the restored windows, provide insulation and didn't require any structural alterations.
I also got storm doors which are not historic but their installation did not destroy any existing elements.
Old sreen and door saved in garage.