I used to work for a CA based company and would extend my business trips out there often. My goal was was always to add some sailboat racing to my business trips. I like "outside" more than "inside" so I wont be recommending buildings or museums but rather scenic vistas and interesting locations. Here is what I would do if I were you...
Land at SD Airport and get a car you like.
#1 Head straight to Cabrillo National Monument
#2 Ocean Pier in San Diego. Ocean Beach Pier, 5078 Niagara Ave, San Diego, CA 92107
#3 Oceanside, CA to The Oceanside Yacht Club 1950 N Harbor Dr, Oceanside, CA 92054 . This can be optional for you but would be required for me to visit my newer friend from Oceanside who now owns the boat my close Ohio friends owned back in the '90's. Yeah, I race the same exact boat in CA that I raced for years on Ohio, Lake Erie. Find an older 39 Ft sailboat named Knot-a-Clew.
#4 Dana Point Harbor. Point your GPS to The Chart House, 34442 Street of the Green Lantern, Dana Point, CA 92629. Not so much a recommendation for the restaurant as a recommendation to get high on the hill to see the whole harbor.
#5 Stone Brewing, 1999 Citracado Parkway, Escondido, CA 92029
#6 Home to hotel in Temecula which is about 30 minutes from Stone Brewing Bistro
Map representation:
Expanded detail:
Cabrillo National Monument :
https://en.wikipedia.org/wiki/Cabrillo_National_Monument
The Monument is 24 minutes from the Airport. This will put you high on a hill. Look to the east and you will be looking down on the sky scrappers of Downtown SD and all the San Diego Bay. Look to the West and all you see is ocean. Look to the south and you can see as far as Mexico. See all of the military presence in San Diego Bay with ships and planes. You overlook 2 airports. One that you landed at and the other all military.
The actual park is this green space:
Ocean Pier:
It will take about 20 minutes to go from Cabrillo to Ocean Pier. All a drive through town. I choose the pier because you can walk all the way out there and get a good way "into the ocean". You will see lots of surfers around the pier and general "beach life". http://www.oceanlight.com/log/ocean-beach-pier-san-diego.html
Oceanside Yacht Club: Not because it is great but because I have a personal attachment to there. Look for a 39 Foot sailboat named Knot-a-Clew. Located in boat dock #J21.
This is a crappy photo of Knot-a-Clew. The one with the Stone Brewery gargoyle on the spinnaker. Yes, officially sponsored and endorsed by the brewery.
Oceanside is the northern-most part of San Diego County. Next stop is Dana Point which is the very southern part of Orange County. Most everything between them is the Military, Marine Base Camp Pendleton. The hyw headed north is called the John Basilone Hyw named after the famous WW2 US Marine who happens to be a distant relative of my wife's who's madden name is Basilone.
As you drive between the two ports the hyw continues about 20 miles through Camp Pendleton. This means that for 20 miles there is really no development on the shoreline. It is a pretty unique stretch of land. It also serves as a reminder of how the whole area looked in years past well before the population explosion of California.
Dana Point. Another pretty harbor. I sent you up to The Chart House, 34442 Street of the Green Lantern, Dana Point, CA 92629. Not so much to recommend the restaurant but rather to encourage you to get up on the hill to see the whole view.
View from The Chart House:
Total aerial view
Also see the historical Brig, The Pilgrim in the harbor.
https://en.wikipedia.org/wiki/Pilgrim_(brig)
From here I send you back a little south and a lot east to The Stone Brewery Bistro. There is no easy way to get there from Dana Point because all of Camp Pendleton is standing in your way. Expect about an hour to get from Dana Point to Stone Brewery. I know you mentioned no need for alcohol but the food is great here too as are the grounds.
Outdoor:
Indoor:
More of their Garden Area:
30 minutes away and you should be at your hotel.