I was out in N. California for a while. A popular route among the locals was to go from the vacaville area, up around Lake Berryessa and down into the Napa Valley. Very pretty. It's also very curvy, and it tests your skills. It's also dangerous because the roads can have water run- off on them and if you lay your bike down you may also be going down over a cliff, People have died/been paralyzed. Get the lay of it first then go back and have fun on it. I can't attest to the quality of the blacktop since I haven't been there in a few years. Also the sac to the bay ride is fun -> sbfreaks.com, if you haven't done that. It's an easy ride, mustly highway, check it out. Of course down the california coast, so pretty. Hwy 1.
Another good (long) ride would be from Phoenix to Las Vegas (Hwy 17 and on) in the spring, then the desert flowers are blooming and they are something else. There are lots of interesting stops/sights along the way. If you are going to/from southern cali to phonix to vegas, then either get one of the loops, the 303, 202 or the 101 through phoenix, otherwise it's a stop light every 100feet on the city streets.
Is that like what you are looking for?