The Santa Rosa area is pretty cool, I used to live there. If you are into beer Russian River is a regional legend. Bodega bay isn't too far off of your route and its beautiful this time of year. its the place where "The Birds" was filmed and you can find decent camping at the bodega sand dunes. The whole area is loaded with wineries too, especially healdsburg. Theres not much between Santa Rosa and the bay. I cant say seen everything but i don't remember anything but a nice drive between the Santa Rosa area and Eureka which is a good chunk of your journey. In northern California 101 forks with route 1, which is a legendary drive full of beaches and tiny ocean side villages. If you do go route 1 Mendocino is a cool place to stop. Its basically a hippy commune but the (organic conflict free fair trade commune-owned) coffee is excellent and its a quiet place to have a relaxing vacation.