[Amgine]

The commercial sail route is, generically, head south of New Zealand, get plenty of easting to make the northbound leg to Hawaii. From Hawaii, nearly due north to clear the Pacific High, then east as the wind begins to favour.

I believe Cornell details these routes, as well as the beat-to-weather-in-the-equatorial-counter-current-for-thousands-of-miles route. The British Admiralty Ocean Passages for the World prior to 1954 has excellent detail for these routes as well.

It might be easier and more interesting to sail the other way 'round. Cross the Indian Ocean, under Africa, up to the Carribean, down through the Panama, out to Hawaii, and then up and over the Pacific High. If you take long legs it shouldn't be dramatically longer, the weather risks would be lower.

Your primary consideration in planning your departure is to avoid regions of tropical depressions during their season. Secondly is to maximize favourable winds and currents. Cornell's books detail these very well. Pilot Charts, which show average conditions in a region during each month of the year over a long period time, are really important tools when you get the basic course laid out. It's just a steady application of research and study to build a set of goals like "cross the Tasman between date and date, and beyond the cape by date; sail east to longitude X in the vicinity of latitude Y, then begin angling to reach X, Y and thence lay a course for Papeete. Leave Papeete by date..."

Of course, financially you'd be ahead to sell your boat, fly to Seattle, and buy a boat there. But where's the adventure in that!