Pemberton is 4000 x 75 ft paved. Dash-8's can easily land there. There's no instrument approach, though, and the surrounding terrain is very close and high, so weather could be a problem. Also, it's 25 minutes by car from Whistler when the roads are in good condition. Time wise (time to the airport, time in advance of departure that one must arrive to check in, flight time itself, and ground transportation at the other end), it would only make sense for people who are already at YVR arriving on another flight and would be connecting to Pemberton. Even then, it may be quicker to just take a bus from the airport. I think some people would still want to take a flight though as it's flying and not driving.