R&D, you might want to fetch a reprint of a recent (2004) Practical Boat Owner (UK mag)that reported on a family that did the Northwest Passage route. They were reportedly the only boat to get through that season despite a number trying. It wasn''t so much about tough water and big storms but rather dealing with the vagaries of the ice pack and resulting uncertain navigation. You can start the search at http://www.ybw.com/ybw/home.htm
I mean no offense but I think you are grossly underestimating the challenge, even if you''re gung-ho to attempt it.