The Rab/ID eVent shells are about ideal as year-round hard shells. I can generally wear one almost as a windbreaker (almost...), & the fabric's tough enough for any season... at 10 ounces, not bad.
That said, for deep winter I usually just use a windbreaker. If it's 0*F it's not gonna rain, and I'd rather work on moisture management w/my layers. That said, if I know I'm going to be spending a ton of time rolling in the snow, ice climbing, etc then I might go for a hardshell. I do like Paramo-like garments for those conditions, too.
Always struck me as odd that Patagonia, for example, offers Houdinis during the summer months and not winter. In summer I'm guaranteed rain and soak-thru on a windbreaker. In winter, I get better breathability w/little concern for soaking thru w/the windbreaker.