I know you love to be in Wisconsin but it would sure be easier to go south for the winter and return in the spring! I love Wisconsin too but I used to snowmobile up there and it is beautiful but very cold. You could probably get to Texas for $500 in gas which might be cheaper than your heat bill there. At ant rate, you said you did not want to cover your windows with plastic because you wanted to be able to see out if you wanted. Have you thought about the kind of plastic that adheres to the window frame and then you heat it with a hair dryer and it shrinks up tight? It is almost crystal clear just like glass. Wishing you the best of luck in what you do!!
P.S. It gets very cold here in Ia. too and is 18 here right now.
