You can launch in Wilsonville - there's a couple decent spots you could put in a yak - one at the city park near city hall, the other at the dead end of Boones Ferry Rd west of I-5. I've fished there from the bank and done very well on smallmouth, and fished that stretch from boats as well. If you avail yourself to the two rod endorsement and choose to fish a meat line with say, a big nightcrawler or a hunk of fish - you might be surprised at what you catch. Caught sturgeon, BIG squawfish (pikeminnow), and channel cats in that vicinity. Or you can put in at the marina on the south side of the river if you want an easier launch, but you'll have to content with quite a bit of boat traffic, and I think there's a fee to use the launch.
Rogers landing is very nice - good mix of small and largemouth bass to be found up there, as well as crappie.