The more you tell us, the more expensive it's getting.. have you noticed that :laughing:
I have about 250 feet of actual driveway, plus parking area for the barn and cars in front of the house. The L3400 with bucket and rear blade takes about three passes to plow the driveway, plus a few more passes to clean it up. That's 4wd with rear ice chains, so there's no struggling to get through moderate drifts, not much wasted time. You soon learn to do it in a definite pattern, otherwise you spend more time and waste fuel.
Before the barn addition this year, clearing out after a "normal" storm took me about 1/2 hour if I was serious about getting it done. I expect the barn will nearly double my time, so if I wanted to be out the door by 5 AM, I'm looking at getting up at 3 AM, getting dressed for snow while the tractor is warming up, then spending an hour plowing out. Allowing a few minutes to put machinery away, I'd be scampering around jamming some breakfast in and then getting changed to go to work. A serious dump of snow takes a little longer, and a bad Nor'easter is another thing altogether.
If your area is as large as I think it is, Jay is right, don't even consider the B series Kubotas. In fact, the L series may be on the light side for Vermont snow unless you have some more time. You may want to look at the MX series simply because the job would get done faster. More HP, bigger bucket, etc.
A snow blower will help a lot, you only move the snow once if you plan ahead. Front mount blowers on bigger tractors eat up cash in a hurry, rear mounts are more reasonable, but you have to get what you personally need to do the job.
The price jump between B to L to MX isn't as steep as some think if you take it one step at a time. Personally, for what you have planned overall, the B isn't really an option except for a second machine to tidy up with. I have a smaller operation than you do, and the L3400 is as small as I'd want to go. I'm only speaking to the Kubota line-up, since that's the one I'm most familiar with.
Do you have any plans for hay supply, since there are horses involved? If you need to buy and move round bales, you need to pay close attention to lift capacity on the loader. A typical round bale of horse hay will run from 600 to 1000 lbs depending on size and density, and that's a serious handful for a compact tractor. We use square bales only, but can handle small rounds if we had to.
Sean
Add to that the need to leave the house by 5 AM 4 mornings a week. Would need a RELIABLE early bird who would be careful around the fences and 130+ Y/O barns. This isn't just a driveway thing. Though I have to say, the idea of getting up early enough to do the minimum required snow removal in time to leave by 5 doesn't seem pleasant. 
