Pooks, when I lived in Seattle and was just starting out, I used the paved bike path for a LONG time. Then, with my then-husband's help (he was more experienced), I started venturing out into urban traffic behind him. Later, I found I could go to it alone, and I got used to truly urban riding. I don't love that, though.
Now I live in a more small town area, but the traffic is on the rise. It is a rather interesting thing because we literally only have one highway into town and one highway out of town. We are squished between mountains and salt water, on a peninsula. So, for long routes, it is either all the main highway, or climbing the foothills.
Mostly my challenge is finding a route with only as many hills as I want that day. So, some days I drive my bike out to a flatter area about 30 minutes away, and I ride in the country, although still a lot of traffic.
Other days I ride out my back door and in 5 minutes I am heading up into the national park climbing up the local mountain. That is a serious climbing day. the first 6 miles take me up 1600 feet of climbing, and it only climbs up from there.
Other days to do the longer loops there is no avoiding the 2-lane highways, complete with RVs and loaded logging trucks. I just wear my ID, use my helmet mirror, and wear bright yellow.
"The best rides are the ones where you bite off much more than you can chew, and live through it." ~ Doug Bradbury