Marc,
I will try to answer your questions as best as possible. Normally New Hampshire gets a great deal of snow, this year has been a very marginal year snow wise.
I am actually the last person you want advice and knowledge from on what size and HP tractor to do ??? jobs.
Although I grew up on a small working farm doing haying, plowing, harrowing, firewood etc. and have been around tractors most all my 40 yrs. This is the first tractor that I have ever owned and I have only owned it for 1 year.
It is also the first year I have EVER plowed snow with ANYTHING !! But, I am pleased to say that my 950 MFWD with 27 HP (per manual) and turf tires has performed flawlesly in keeping my yard clean.
I have attached a picture of my yard taken from my neighbors driveway, unfortunatly there is no place where I can stand to get a picture of the Whole driveway and yard, but the pic will give you an idea of what I plow.
My driveway continues off to my left up to the main road, probably another 300', as you can see my driveway is actually a big tear drop with a good size parking area. I hate snow banks, So where possible I push the snow all the way to the tree line.
With the front blade, it probably takes me 2 hours to plow and clean up the way I like it. 1- I am in no hurry (seat time), 2- I am a fussy SOB. A friend once told me that they could use my yard for Super Bowl overflow parking.
I personally don't see the need of owning a snowblower for what I do. My front blade does an excellant job.
I am positive that there are other members here that are more knowledged and can help you in determining what size tractor would be best suited for your needs, for I am sure that plowing snow is only one of many jobs you will be wanting your tractor to do.
27 horse power with 4wd and proper weight will surprise the heck out of you with what it's capable of doing.
I hope this has helped and not just confused you or put you to sleep.