That really depends on weather and air quality. I prefer my sunsets to have some clouds to add some color, texture, and contrast to the sky. Air pollution also tends to create more vibrant reds. I'd say anywhere in LA would work. SEKI is inland and by the time you get south enough to get "easy" beach access, you're at Ventura or Malibu. Actually, Malibu would be nice.
I like contrast and colours too in my sunsets. Is Malibu a nice beach to take a long walk? We're used to FL beaches but it's our first time in California and we want to see the Pacific a little.