My profile is similar to yours - 30 mile round trip and 6'2/220. Daily year-round commuting in Silicon Valley. My trip takes between 51-55 minutes each way, depending upon traffic and lights and how frisky I'm feeling.

I ride a Specialized Allez Elite with a rack on the back. I only use the little ring on very occasional weekend rides up into the mountains, and I only use the big ring on downhills and tailwinds, so the middle ring gets all the mileage. I could probably get along fine with a single front, but why bother since it's already there?

About riding on the road with cars - that's a skill you can learn, and with skill comes comfort. For starters, read Street Smarts. If you'd like more info and hands-on instruction, take a Road 1 class.