In addition to Ano Nuevo, the seals can also be seen near Pt Piedras Blancas near San Simeon/Hearst Castle. Less formal and parking can be an issue, tho. I think these are the only two places on the mainland they come ashore.
Not by that much. The 101 and the 1 are the same road out of Santa Barbara. Split off at Las Cruces, hit Andersen’s, then take the 246 back to rejoin the 1 at Mission Hills.
I forgot one, though it is kind of at the beginning of the trip. The Getty Museum is great - free, but you have to reserve parking in advance. However it would blow most of a day, so there might not be time for it.
Absolutely worth it and, as silenus points out, it isn’t much of a detour.
I used to live in Solvang. It is a really cute town. Ton of wine, if you’re into that. Plus, there’s a restaurant that I suggest: Grappalos. Amazing food and even better service. That’s where my wife and I had our wedding reception.
And Solvang is definitely on the way if you plan on going to Andersen’s.
Be warned that San Simeon has several different tours and that they usually require advanced ticket purchase. Check the web site for details.
Lots of good suggestions here, but I would recommend doing the drive north to south, from SF to LA instead. That way, you’re always on the ocean side of the road and it’s much much easier to pull out when you want to enjoy the view.
There are all kinds of “lesser” sights and attractions between the Bay Area and La La Land. South of SLO is Montana de Oro State Park and Los Osos Oaks State Reserve. Just down the road from Buelton and pea soup is a really cool waterfall (depending on recent rains) at Nojoqui Falls Park. In Cambria you can visit the Nitt Witt Ridge, aka “The Poor Man’s Hearst Castle”.
In between King City and Hwy 1 is Mission San Antonio in the middle of Fort Hunter Ligget–the road passes through some wonderful undisturbed oak woodlands, and you can drive all the way to the coast on a narrow road with fantastic views. Just south of Carmel is Point Lobos State Reserve, once described as “the greatest meeting of land and water in the world”.
So obviously you won’t have a problem finding neat places to check out. How much time did you say you have?
The last time I went by Harmony it was for sale. Might still be for all I know.
What no recommendations for going over the Grapevine, Bakersfield, Freso, Modesto and then over to SF? I’m just sayin’ 
Seconding this. I cycled the coast and there are more turnouts/easier to access view points going south. The bike lane is also wider as it assumes most cyclists go north to south (due to prevailing winds in the summer).
Yeah, no trip to California is complete without smelling that cattle ranch on 5. (Insert hold your nose smiley here.)