Part of the 4 square feet per chicken is to give them enough room so they don't go cannibal if they are stuck in there a lot. Part of it is to handle the poop load. Part of it is to give the chickens room to get to the feeders and waterers and give you room to put the feeder and waterers away from the roosts so they are not pooping in them.
If you feed and water outside, you eliminate the component needed for them to get to the feed and water. You also reduce the poop load because they don't spend as much time inside. The food needs to be under your cover where it will stay dry. If you put the nesting boxes outside the coop, you give them even less reason to be inside. About all you are using the coop for is a roosting area.
I grew up outside of LaFollette. With your climate, the birds will be able to go in a covered run practically every day of the year unless the climate has gotten a lot worse in the last 30 years. If you do not leave them locked in the coop after daylight so they can get to the food and especially water when they wake up, 2 sq ft per chicken should be enough.