There are also comparatively very few people who live in the Redmond area and who commute to work downtown Seattle. It probably shouldn't be a heavily serviced path, realistically speaking.
Maybe before the new 520? There are now continuous bus lanes for most of the 545's route.
Seconded, the new HOV lanes on the 520 have made the 545 a much more bearable option than it used to be.
During regular working hours? No way! 545 is awesome and takes ~30 minutes to Seattle. So an hour is more realistic. Even carpool is not bad with much better HOV coverage.