Looks like you've made your decision.
I was going to pop in and make sure you were comparing apples to apples! I once chose to fly into ONT, after checking ONT vs SNA, and checking Super Shuttle's rates from SNA.
Whoops! SS's rates from ONT are *significantly* higher than from SNA, and I lost most, if not all, of the savings of the airport by not checking it all out thoroughly.
With your SS calculations, I don't know if it makes a difference with a private shuttle, but check anyway...they show lower rates online if you use the hotel name instead of the zip code. So use the hotel name!
You're probably using Jet Blue or Alaska, but just in case, be sure to check out Virgin America's rates as well! Now that both VA and Alaska are (or will be) charging $15 for the first bag (Virgin currently, Alaska starting in July I believe, with bookings after May something) they remain neck and neck, and VA is so lovely to fly on. Of course JB still has first bag free (but I personally haven't enjoyed flying with them).
As for the time inside the airport...the one time I flew out of SNA I got there mega early b/c of SS, then my flight was delayed for hours. The times we've left LAX, the staff are lovely and helpful (with Alaska you have to take your bags over to the xray thing/conveyor belt, and the last Alaska person actually helped hubby do that), the TSA folks are serious but kind (though their metal detectors are ridiculous; my 1.5 inch barrette set it off once!), and I haven't had a hard time finding my way around to and from the gates (I just get turned around inside their circular gate area).
And of course a benefit OR downfall of LAX is the possibility of celebrity sighting and/or accidentally being in the background on TMZ later than night.

Depends on your outlook if that's good or bad.