I love winter riding, haven't had mechanical related issues just took a couple spills on the real sloshy stuff. You may want to make or buy handlebar windscreens since even with very thick gloves the cold still creeps in. I wear a full face helmet which tends to fog over no matter what I apply to it though I can crack it open a tad and the flowing air usually clears it up.
Blizzard or snow weather is harder to ride in for obvious reasons, and I find if it's cold and wet enough my carb will frost over and it can slow the bike down to 10ish mph. This is from the fine snow icing the carb out so if it isn't actually snowing (or you're not rooster tailing through mounds of snow) then it won't happen.
I use a jackshaft so the gears are less important, also the gearing itself doesn't make a big if any difference, if you have enough power in dry weather then you'll have enough in snow since traction isn't the same as gearing, if you can't get it up a hill with snow it's because the bike really litteraly can't go up the hill because it's just slippery, the studded tires are an option, I've looked at them probably a hundred times over every winter yet I keep managing to get by without them, I don't seem to be crazy enough of a rider in the winter to need them and the wider 3 inch (more like 2.5) tires I sport handle well enough.
If I really wanted a winter rugged bike I'd pick a 4 inch wide wheel since you can drop the pressure down to 5psi and have a large grippy footprint with nearly as much traction surface as a car tire. Studs are really only good on ice, and that's a challenge in itself to ride on even with studs.