We just got a ton of snow in New England.
Since the subaru AWD + snow tires are really a cracking combination on my impreza, I have a couple of suggestions to make a winter package.
1. Wipers keep freezing. Pipe some engine heat up where they rest to keep them clear. It's horrible to have a great drive system, but have to pull off the highway to de-ice the wipers so you can see.
2. Rear wiper. Defroster is great, but there's no substitute to keep your rear visibility useable.
3. A little more steering feel. Useable on dry, wet and snow. Porsche like feedback would be great to keep those winter slides under control.