Coming up in just over a week is a trip around Southern California for our first wedding anniversary. We're flying into & out of LAX, but from there will be driving all over to Santa Monica, Long Beach, Joshua Tree, Palm Springs, San Diego, Laguna Beach, Anaheim, DTLA, Hollywood, Thousand Oaks & Malibu. Anticipated freeways we'll hit include the 5, 8, 10, 15, 60, 91, 101, 105, 110, 215, 405, & 710. In particular from that list I'm looking forward to checking out the Arroyo Seco Parkway & the Figueroa Street Tunnels, as well as the Vincent Thomas Bridge & Long Beach International Gateway by the ports.
If you're going to Thousand Oaks, you'll also likely be on the freeway portion of CA-23. Thousand Oaks isn't that exciting, although if you are continuing on to the Oxnard Plain (and places like Camarillo or Ventura), well, I'd recommend that. Some nice beaches in Ventura and the weather is always good.
Specifically, why not drive the entirety of PCH from Dana Point to Oxnard? You'll go through Malibu and there are some great views. Some famous beaches as well, including Zuma. Point Dume is a good stopping point, you can park and walk up to the top of it, there are some short trails in the area.
Looping back to this now that the trip is complete:
Main reason Thousand Oaks was on the list was that I have extended family there - didn't go any further west or north beyond there, and didn't utilize CA 23 at all - just US 101.
While we didn't have the time to hit the PCH in one go as you described, we did hit pieces of it on different days - from Dana Point to Laguna Beach one day (and then took CA 133 thru the Laguna Canyon up towards Anaheim), followed by Santa Monica to Malibu another day (and then up Malibu Canyon Road to Thousand Oaks from there). We were on this stretch of the PCH around 6 PM, so we pulled off at Topanga Beach to catch the sunset there.
Overall, the trip was fantastic - might get around to posting some road photos in another thread at some point, but I certainly had a blast driving the SoCal freeways (while strategically avoiding the worst of rush hour). I did end up hitting every freeway on my initial list, with 2 additions: CA 56 & 163 in San Diego. As for major bridges, I added the Coronado Bridge in addition to the Vincent Thomas Bridge & Long Beach International Gateway. As a final side note, LAX terminal 1 is gorgeous post-renovation as well!