I'm sure there are fishers much more qualified to answer your post but since this board does not often get a lot of action and smallmouth are one of my favorite fish to catch I'll tell you what I can. I have not fished Lake Washington but every year think I should. It seems you are on the right track with the baits. Smallmouth like rocks so if you find a rocky point or shoreline it would be worth some time. This time of year I would stick with the slower moving baits, worms, tubes, jigs. I would immagine the fish will be a bit deeper right now probably 15 feet or more. Smallmouth will probably start to move onto spawning beds, look for gravel, in 5 to 10 feet of water in middle April to early March depending on the weather/area and can be in the shallows until late March to early June. People who really know what they are doing say you can see thier beds in shallow gravel areas with some polarized shades. 3 to 4 inch tubes in pumpkin (crawdad) or watermellon (perchy) colors on a Carolina rig should work. I like to cast crawdad and perch colored shad raps in the SR5 and SR7 size along rocky shorelines during the mid to late spawn. Smallmouth are schooling fish so if you find one chances are, there is at least one more around. Later in the summer go back to fishing deeper with deep diving cranks or your jig, tube, selection. I'm not sure if this helped, or is accurate since I have only fished for smallmouth in the Eastern part of the state. Good luck, I'd be interested to know how you do.