Replying to California to BC/Alberta road trip advice

In January I'm planning a road trip from California (Mammoth/Tahoe) up to Whistler and then to Banff, ending in Calgary. I'm from Switzerland myself and have only skied in Utah and Colorado so far in the USA and it will be my first time in Canada.

I'm looking for advice for awesome mountains to ski along the way, especially in Oregon, Washington, BC and Alberta. Please fire away the places I need to look up and consider driving to.

Also, would it be worth it to continue from Banff down to Jackson Hole? Any places really worth visiting along this way?

I will probably have 3 weeks in total, maybe a bit more. Thanks for the help!