I'm planning to book a week at Rancho La Puerta (fitness/spa type place) and will be flying into and out of San Diego. I'm trying to decide if it's worth staying a few extra days in San Diego. I would probably want to see Balboa Park and the USS Midway, I'm not sure about the zoo. What else is cool to see in San Diego? I'm flexible about dates but most likely it will be sometime between March and early June as I have another trip planned for late this year. What is a good time of year to visit? And any recs on where to stay? I would get a rental car. Thanks in advance.