We went to the San Juans this summer. Our base was in Friday Harbor. We made it to Lopez Island for riding, and around San Juan, of course, but after figuring out we would spend all day/night on the ferry to ride on Orca and another day to go to Vancouver Island, we decided to ride less and did some hiking and other historical stuff, in addition to riding. I would want more than a week to do it all, and be able to stay overnight in Vancouver. Taking 4 huge suitcases on the ferry was a pain after flying across the country, and we got dirty looks and comments from people (like we were breaking some "rule")! However, when we said bikes were inside 2 of the suitcases, they softened.
I would go back.