LAX will always be the cheaper flight - from just about anywhere.
John Wayne airport is closest to DLR so transportation will be cheaper.
The Bob Hope airport is a good suggestion from mel2014 - it's small and easy to navigate. Transportation to DLR (Uber/taxi/towncar) will be just a little more than SNA.
I, too, would suggest a towncar over Uber. With luggage the service is worth the extra cost.
When are you traveling?