Well traffic is every where nowadays! If you are on a limited time schedule to get where you are going the Interstates between major cites is likely your best bet, getting through the metropolitan area then is a choice of back roads or stick with the interstate. Going to back roads might or might not save time, but might be more relaxing!!
I had a commute years ago that if traffic was backed up at all, I would take a a surface street at a speed limit of 25 mph. Did I save time I really don't think so, was it less stressful Darn sure!!
PS: To those in the NW, Bellevue to Puyallup commute, I405 SB Kenneydale hill!! Took Lake Washington Blvd. If the Valley FW was bad, West Valley highway!