Advice/Suggestions North West-West Coast to SD

[Chili]

I'm taking 35 Days vacation from the second week of June until the middle of July and my wife and I are planning our first extended trip on the bike. I'm doing research as far as the prep end of the trip but now I'm looking for route and possible highlight stops for the trip.

We will be leaving Winnipeg, MB and working our way across Canada with some family obligations. So far in the planning we we will end up in Surrey B.C. done with all obligations and ready to depart on June 20th with roughly 22 days left on our vacation and this is where I'm looking for tips.

We are looking to head south from Surrey and try to see as much beautiful scenery along the pacific coast as possible. We will likely head as far south as California to see some of the Pacific Coast highway. From California we will start to work West with only a loose plan at this point to end up in South Dakota to see some of the beautiful countryside we've heard of around there and then make our way back to Manitoba.

Any must see's or must avoid routes or side trips would be appreciated!