There is some good riding in Victoria and just to the north - Hartland Dump, Cobble Hill, Mt Tzou. Steve Smiths segment in Seasons was on Mt Prevost. I don't know that these would be great for a SS though you would probably have more fun on a full suspension. A lot of the rides used to be freeride oriented - climb up trail or road and then descend singletrack but they may have more xc trails now. The trails could be more difficult than you're used to as well, blues up there would be black down here, etc. Expect rock slabs, rollers, wet roots and woodwork. I've heard there is trail in Ucluelet and Port Alberni but don't know anything about the riding there.
Hopefully you will luck out on weather but the west side of the Island gets tons of rain. Victoria has a better chance of being clear. You can ride in the rain or after it though, the trails stand up fine when wet. The best bet for SS riding is Hornby Island. You could make that a day trip stop on the way from Tofino down. Its not far out of the way and is an easy ferry ride over. Hornby Island trails are really fun and would be great for SS. There is also great riding in Cumberland and Snowden Demo forest by Campbell River. Those are an hour north but could be an option if the weather in Tofino really sucks. It may rain heavily there but could be nice on the east side of the Island.
