Pretty much anywhere in Washington is safe from violence if you're not in relationships with people prone to domestic violence, involved in criminal gang activity, or involved with illegal drugs. If visible homeless people or the potential for property crime are upsetting to you perhaps avoid urban areas but you're going to miss out on urban amenities.

Having recently moved to Oregon (Portland region) I'm getting the impression that Washington generally has more functional local/state government and better public schools.

Pay attention to what communities are directly connected to Seattle via the ferry system, Amtrak Cascades, and Soun Transit's rail and bus service.