There are quite a few good rides in the Santa Barbara/Ventura area.
I like the Burbank suggestion, too.
On a Saturday morning in Woodland Hills, you are likely to see more cycling traffic than car traffic.

Also, you owe it to yourself to go riding in Caliente sometime. The best kept secret in California hill (mountain) climbs. It's not really So Cal, but it's close enough that you could check it out on a weekend. You're welcome.