Come on guys - it is the Straits of Juan de Fuca, Haro, and Rosario. They are notorious for nasty weather
and surprises. I sailed them for over 40-years and made hundreds of crossings and they still worry me - every time.
The OP is thinking carefully and asking good questions but, eventually you have to go and nothing in the weather forecast
tells me that Wednesday the 16th would be a problem.
I plot, plan, think, and worry - but eventually cross pretty much every time I've wanted to. Some of the trips were nasty, a couple scary, and one dangerous due to sudden unexpected fog
in the central convergence zone near Smith Island with several big fast ships on radar
But, they are just a part of the Pacific NW cruising and boating
Make the trip with a sharp weather eye and a plan to bail out and wait in Makey Harbor or Alek Bay. I've waited for a weather window in each place many times and have enjoyed each time.