SeaPort

There's a new shuttle airline out in Seattle flying out of Boeing Field into Portland. The approxitamely 50 minute flight is will be flown on a 9-seater Pilatus PC-12. SeaPort will only offer flights during the business rush hour from 6:00 - 10:00 in the morning and then 5:00 - 8:15 in the evening. Prices start at $74.50 with unrestricted tickets going for double that price.

I've only flown out of SEA once so I can't speak to the "avoid the hassle" aspect of the flight, but for some I'm sure this will be more convenient. Anytime you can avoid the crowds it is likely worth it, especially since they'll have a robust schedule at peak times. As for comfort, Alaska has Horizon Air running Dash-8's and United has Skywest running EMB-120 props, so it is not like you'll be sacrificing comfort. For what it is worth, they've matched SeaPort's $74.50 pricing.