I'd choose it based on the non airport part personally, but this is the OP's prerogative of course.

FWIW last time I did this journey (which I have done a fair few times as have family in LA) my wife and I flew back LAX >> LAS >> LHR. Shorthaul up front with AA (which was a great flight for one so short) and then BA J on (iirc) an older mid J 747, but we were in an op-up into J so we were happy anyway.

I haven't been to San Diego in about 35 years so I'd be useless at any sort of comparitive reccomendation.