I don’t think skytrain should be extended to the ferry terminal. that route from river rock to the ferry could be first in line for a self driving tram-bus though.
It should be extended to Ladner, say, by 2025 or so, the crossing part built with the new tunnel. From there, eventually a loop over to King George, though that's a couple decades off probably. A express bus system between the ferry and Ladner is easy with one stop around Tsawassen Mills.