The best part of Calif. HWY1 is on the north of San Luis Obispo. For me, I don't think any portion of the coastal line south to the San Luis Obispo is worth a stopover with compared to the former.
IMHO, you should go out of LA area asap after arrival at LAX, via 405 and US101. You might want to have a layover at Santa Babara, Pismo Beach area before you get San Luis Obispo area, but my suggestion is to avoid any excessvie stops along the way. You probably can stay over a night around or north of San Luis Obispo. The best portion on your HYW1 trip should be from San Luis Obispo to Monterey
IMHO, you should go out of LA area asap after arrival at LAX, via 405 and US101. You might want to have a layover at Santa Babara, Pismo Beach area before you get San Luis Obispo area, but my suggestion is to avoid any excessvie stops along the way. You probably can stay over a night around or north of San Luis Obispo. The best portion on your HYW1 trip should be from San Luis Obispo to Monterey