Kevin-- I've spent a lot of time in the Strait, from Neah Bay to Port Townsend, most of it in boats under 16 feet in length-- in fact, I started in a 10-foot Livingston. If you've run a Stratos, and you're wise enough to be cautious, then you should have no real problems running out of Sekiu.
Often the silver fishing is close in-- you can almost always find some fish near shore, so it's not like you have to run 20 miles to find fish. Also, Sekiu has some of the best boating conditions on the Strait-- when it's rougher than a cob in Neah Bay or PA or PT, Sekiu can be pretty flat. Caution is a good thing, but I wouldn't let too much keep me from fishing in the late summer and fall-- as long as the weather forecast and your weather eye say it's OK, then it probably is.
There are a couple rules of thumb that you might use as guidelines: first, it's generally calm in the early morning unless there's a tide change. Second, the afternoons are when the wind kicks up, so you want to be closer to port later in the day. Of course, there are days when it blows all day and days when it's rough in the morning and flat in the afternoon. Usually when the westerlies blow in Sekiu, you can fish in the bay, and the water is rough, the silvers will be closer to the surface.
Neah Bay is pretty good as well, except that I don't think there is much of a rental fleet left. I've only seen a few boats at Big Salmon, and I don't know if any other place has rentals. I like NB because when the silvers are in thick, you don't even need to leave the harbor, and you can also score big on rockfish at the same time. However, the winds tend to make the area outside the bay pretty rough at times, and if you're antsy about your boat-handling ability, then you'd be better off at Sekiu.
But be careful; a few trips to either spot may find you looking for your own boat in short order. The fishing is pretty addictive.