This was our 4th cruise with Carnival, all on different ships but this was the second on the Spirit Class.
Got to San Diego 2 days early, as we were coming from Alaska and you have to plan for possible flight delays and/or cancellations. Stayed at the Holiday Inn by the Bay. Hotel is a little old, but location makes up for anything. Right across the street from the cruise terminal, close walking distance to museums, nightlife, eateries, etc... Highly recommend if you are cruising out of San Diego that you stay at this hotel.
Embarkation seemed confused and disorganized. You would think it was their first time. Hundreds of people waiting for the call to head to the ship, but only enough chairs out for about 1/3rd of them was the most glaring issue. But all in all not bad, was on the ship within a couple hours.