This might be a late response to this thread but I've lived in the Seattle area my whole life. 18 years, doesnt seem like a lot but I'm in Seattle everyday. People are right when they say traffic sucks and people are really predictable when they drive but if you know how to drive yourself then it shouldn't be a problem. Also its easy to take back roads and find your way around the traffic.
The car scene down here is decent. Theres actually street races and car meets every Fri, Sat, and Sun if it doesn't rain. It goes until early in the morning. You also don't have to street race and get in trouble. You can just chill and talk about cars or whatever. Hundreds of cars show up. Get at me if you wanna find out where they are.
But living in downtown is the most relaxing place to live. I love it here in Seattle. Its not even that far to Seatac, Tacoma or Auburn from downtown.
There are some pretty sick festivals such as The Bite of Seattle and Bumbershoot which is a music festival. We also have Seafair with hydroplane races and another big music fesitval at the gorge which is like quite a ways from Seattle but worth it. Music is obviously a big part of Seattle.
People here are cool. You obviously have to pick the right people to talk to but they are generally friendly here. Like every city there are some weird people but it only makes it more interesting. Its not typically dangerous to walk around at night either. In downtown theres a look out point that shows an amazing view of the space needle and the buildings around it and if that isn't beautiful enough for you, you can take a short drive to Alki beach which has the best view of Seattle you can find. On the weekends theres always nice cars down at Alki as well.
Lately the weather has been gorgeous but when it does get cloudy and rainy it is a bit depressing.
Overall I think Seattle is an amazing city and I'm suprised it isn't more popular then it is. Honestly I'd recommend moving here.