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I cant quite tell from your description the orientation of the garage. If any wall on it is facing south I would recommend windows there as well.

Wind - check out this site. I do not own one of these, but if I were building right now I would seriously consider combining this with PV. Often when the sun is not there the wind is. They are a great complement. http://www.mikeswindmillshop.com/product-category/wind-generators

For solar electric look here:http://sunelec.com/
Solar panels are SO cheap now. Less than one tenth the cost of fifteen years ago. If you are willing to do-it-yourself a bit, the payback is very quick. For example see these at 34 cents per watt. http://sunelec.com/solar-panels/tianwei-90w.html

The geothermal heat pump costs vary considerably on the site. New England is rocky and ledge is common. These can make costs very high.

I hope when you say central fireplace you actually mean central woodstove. Fireplaces do offer thermal mass advantage but that is offset by terrible efficiency. A masonry stove is a beautiful option. It is VERY efficient, Very clean burning, and great thermal mass, but they must be custom designed and built for the site and so are expensive. see https://mainewoodheat.com/masonry-heaters/

Depending upon your thermal mass, insulation, and amount of south facing glass per sq ft., a single wood stove run on cold winter nights is normally plenty for every 2500 sq ft of house. This also depends upon layout and ability of heat flow. I designed mine especially so that the heat flow from one wood stove would heat the whole house in a pretty balanced distribution.