That's all pretty south, so your cycling could easily also include SOnoma/Napa as well. I can say that Hwy 128 from the coast all the way to Lake Berryessa is just about one of my favorite cycling roads ever. The Mendocino part from Boonville to the coast is beautiful.

I'm doing a 200k this weekend that will take me on new roads I haven't ridden around Ukiah - I am really looking forward to it. I don't think you can go wrong in the areas you're looking.