A few things to consider
If you are not renting a car it is FAR cheaper to use the shuttle/taxi from SNA than LAX (Taxi from SNA 35.00 vs LAX 65.00, the only cheap shuttle I have found it Airport Bus for 25.00 round trip fromLAX, but I have not heard good reviews of Airport Bus)
IF Southwest flies out of your city, they often times release 50.00 one way fairs from their cities, MONTHS in advance. I recently got 50.00 one ways from Boise to LAX, so 100.00 round trip. That is the CHEAPEST I have ever seen the rate. We fly to Las Vegas a bunch and I can never get that rate under 150.00 round trip, but I bought my March tickets in November.
Make sure if you buy a package from a travel company that if the price goes down before your trip, can you get a price adjustment. Some are allowing this and others are not. Get it in writing. Since you are planning a year from now, you never know what prices will do.