Tips for Pacific Coastal Highway(s) road trip?

Its been my dream for a couple of years to do a trip down the pacific coast starting in northern Oregon and ending at a particular pier in San Diego, taking as many coastal highways as possible, and have the chance to do so this summer with my boyfriend. My mental idea of this is taking like 3-4 days down, stopping at towns and surf spots and doing a lot of camping and hiking, then driving back up 1-5 after spending a day in San Diego. I just want to know if people have specific tips about such a trip, best places to stop? Places to avoid? Am I insane for wanting to do this? Should I budget more time? Any and all suggestions appreciated!!