Welcome to the forums, Mark ::
How much time are you talking about?
What has your research so far turned up and of that research, what appeals to you, and what doesn't?
Will you have a rental car?
December here will be cold, grey and wet. We don't get a lot of snow in Vancouver but the local mountains will have some in December. Whistler will be very busy over Christmas break with skiers and partners.
Victoria might meet your criteria. It will be very quiet out of tourist season, it claims to have old world charm. It has natural beauty. You might even consider driving to Tofino for the wilderness there.
TA is quite a resource when it comes to planning. On each and every forum, you will find to the top right the Top Questions containing much helpful information. In the left sidebar you will find Things to Do - including tabs for Attractions and Tours. At the moment only you know what your interests are, so browsing through the Things to Do will be helpful to you.
The Vancouver Forum. Victoria Forum, Tofino Forum, Whistler Forum would be good places to,start. Type those 2 words into the search field above the green navigation bar to go to those forums.
Our online tourist website is helpful: www.hellobc.com
I'm thinking Victoria might appeal to you. But as always, the more information someone provides, the better the advice will be.
If you flew into Calgary, you could consider the Rockies too. Banff would be the largest place, with enough amenities. Canadian Rockies Forum would be the place to,look for,that. Christmas might be very popular though, and therefore very expensive.