I've described a number of elevated highways (At least three high in some places!) in the city with my group, none have complained or called me on it in any way. Considering how tight and congested Seattle is due to having no room to grow, it makes sense to have them to facilitate traffic patterns.
Downtown Seattle has a Monorail (You see it in the SNES Shadowrun game, actually, it's a nice way of piecing the city off, actually), and it was a minor part of the Archology Shutdown (Well, major to the people who were stuck on the last train into the Arc!).
My group has never taken the bus, but constantly take cabs (Ghoul Cab being their choice when going from/into the Barrens.).