During all of my ski adventures last winter, across both British Columbia and Tahoe, my apparel of choice was the Millennium Blur Pants and Millennium Blur Jacket from Columbia Sportswear. Waterproof yet breathable and fully insulated, you don't need to wear much else to keep you riding happy in all kinds of weather. Not to mention the fantastic Hibiscus color of the ski pants.
The Omni-Heat Thermal Reflective lining of both the pants and jacket works to heat you up quickly as you start to move. In Whistler, I found I only needed a very light baselayer under both the jacket and pants. Even on days with a strong, cold wind or after spending a long time on the chairlift, I quickly warmed up as soon as I started moving. During a particularly cold spell up in Tahoe, where temps hovered into the lower teens at the top of the mountain, I simply added a fleece mid-layer to remain comfortable outside for the entire day.
A combination of zippered leg and pit vents come handy for a quick heat dump when you are skinning uphill or working hard in deep powder. The Millennium Blur jacket offers plenty of secure pockets both inside and out for storing snacks, extra goggle lenses, camera, phone, and money for a full day on the mountain. A small zippered pocket on the left arm cuff is just the right size for storing my Epic Pass for the season.
For deep powder riding, I would love Columbia to figure out a way to hook the Millennium Blur Pants into the snow skirt on the Millennium Blur Jacket or add the Back-Up waist found in some of their other ski pants. Granted, I did spend more time in, instead of on, the snow during our heli-skiing trip in Whistler, but I ended up with soaking wet ski pants by the end of the day- not exactly pleasant and something that could lead to a dangerous situation in colder conditions. I guess an easy answer for the future would be to wear bibs in deep powder conditions.
The internal leg gaiter of the ski pants kept snow out of my boots, while the cuff guards added an appreciated extra level of durability. Bottom leg zips made it extremely easy to get ski boots on and off without any struggle. The Millennium Blur ski jacket comes with an insulated hood- nice for general winter wear but removable in case you don't like to ride with a hood flapping around.