Planing to do San Diego in a day. Hubby and boys want to do USS Midway in the morning. My daughter and I want to do Old Town San Diego. We will then meet for lunch, and do San Diego Zoo in the afternoon and early evening. Finally, we will end up at Sunset Cliffs to watch the sunset. Does this seem do-able? Is there enough to do in Old Town San Diego for about 3-4 hours? Any other better ideas? Thx!