I felt the same way until I cruised down MLK with a group a couple of months ago! I always took the esplanade or crossed I-84 at 12th and meandered through the blocks to get places. Turns out, MLK has a lot going for it!
It's downhill, so your speed integrates with traffic nicely. Most of the lights are timed, so you get to blast through town without stopping for quite some distance. And it's so much easier to make a lot of connections from MLK. I recommend trying it out sometime with a group of experienced cyclists.