Rush hour traffic in the SF and LA area should not be a problem, being a Saturday. Your choices are:

1) East from SF to I-5, then south to LA.
2) South from SF on I-280 to San Jose, then US-101 to LA.
3) Same as 2 to Salinas, Hwy 68 to Monterey, then Hwy 1 through Big Sur to San Luis Obispo. Rejoins US-101.

I've listed them in order of improving scenic interest but also increasing drive time. I-5 will take you 7 hours to downtown LA; US-101 about 9 hours; Hwy 1 about 11 hours. These times do not include stops for meals, sightseeing, etc.

It just depends if you want to get to LA quickly through fairly boring scenery (the last 120km into LA are more interesting mountains), or if you have plenty of time (Hwy 1 is one of the world's most scenic drives).

We do not have speed cameras in California on State or Interstate routes. (Arizona has them everywhere!) Cities may have speed cams on their streets and there are often "red light" cams at intersections.

As mentioned, the police use radar and aircraft. Most police motorcycles and cars have radar that can measure the speed of oncoming cars...so don't think the officer cannot get your speed because he's going the other way on a highway.