The ferry from Anacortes to Sidney Vancouver Island has had a special for RV's. The special rates are half the Port Angeles/Victoria run. Entering Canada via this ferry is usually quick and friendly.
Every Sat night, during the summer. the Butchart Gardens has a fire works display second to none in the world. Check it out.
Diesel and gas is usually 3 cents a liter cheaper on the North/ West side of the Malahat.
Vancouver Island has recently beat out many tourist Islands for the best accommodation, things to do, and places to dine, esp seafood.
The West Coast of the Island is quite accessible with the toad doing day trips with circle routes in some cases.
Victoria is the capital city of British Columbia.It is a wonderful place with ocean parks (pedestrian) the legislative buildings, the down town waterfront, high tea at the Empress Hotel...Cruise ships tie up at Ogden Point and are frequent during the summer.
Four days on the Island is minimal for a foretraveler. Tom