Well, we don't have cold winters here, but we DO have hot summers.
I wouldn't pay much of anything to get better temperatures, even in the summers. In 2017, we are not living in a covered wagon train or a mud hut. We have excellent climate control in our houses, cars, the gym, and in all the businesses and restaurants that we patronize, and so on. The only time we experience unpleasant weather is for about 10 feet from the car to wherever we are going.
Now, maybe it's different in the North:
(1) You'd have to pay someone for snow removal (but then down here, we pay for incessant lawn mowing).
(2) You might slip and fall, or even break a hip, on the ice and snow (but then, even I have heard of YakTrax and that would be the first purchase I'd make if we ever lost our minds and moved north).
(3) You might have more power outages than we do, due to ice, but my perception is that most houses up north do not heat with electricity, plus they have a fireplace or wood stove too. You could get a generator for other electrical needs during an outage.
(4) You can't do much gardening in the wintertime (but here, gardening pretty much consists of hacking back vegetation, back breaking work that is required weekly since we get outrageous jungle-like growth; I have never intentionally planted anything in the 20+ years since I moved to South Louisiana, and that's not uncommon).
So what is your biggest objection to the cold? This is an honest question since I have not lived in "snow country" since the mid 70's. All I remember is being afraid to drive after spinning out on black ice once. But you are used to driving on ice by now, I would expect.
Would having the insulation on your home "beefed up" so that you can be nice and toasty warm all winter, make you happier than moving to North Carolina? If you are really thinking of spending $100K for climate alone, why not invest that $100K in insulating your home, getting a better heating system for your home and garage too, and hiring someone to shovel the snow so that you don't have to?
It sounds to me like your present home has a lot of qualities that you really like, and if you move you might miss all of those great qualities and regret it.