For vis in the local area, Three Tree Point (North) seems to have consistently better vis than most local dive sites. I was just there this morning and vis was 25-30 feet. Not a whole lot to see this time of year but we did see a few octopus (one in a large Vodka bottle) and had a brief encounter with a harbor seal. A couple weeks back we had a less-brief encounter with a large sea lion ... got buzzed several times, in fact.
Vis is really variable around the Sound this time of year, and there's really no predictable way to say where it will be good or bad. I've seen some days recently when it was 50 feet or so, and the next day it'd be half that.
As for BC ... you can't beat Vancouver Island. Nanaimo has some incredible diving and some really nice vis. I was up there in early November and we had 70 to 100 foot visibility. The articial reefs (Cape Breton and Sasketchewan) are great dives, as are several of the walls and reefs.
Someone mentioned Porpoise Bay Charters up in Sechelt ... great outfit. Sechelt Inlet has some fantastic diving, and this time of year you may get 100+ foot vis if you hit it right. Again, a bit of rain and runoff could easily drop that down to half as much. It's the luck of the draw sometimes.
If you're local and looking for someone to show you around drop me a PM ... I've got over 700 dives in Puget Sound and would be happy to show you a dive site or two ...
... Bob (Grateful Diver)