I don't recall the freeway shoulder being bad. It got narrower over some bridges, and ODOT coned off a lane at those spots, but it was plenty of shoulder in any case. They just had the "2000 cyclists on the road" thing to worry about.
I see I mistyped up there - we were on the freeway shoulder from Hood River to Wyeth, and exited at Wyeth.
I don't think there are too many exit ramps that you need to worry about.