Lots of PHX to SFO WB commuters and not a ton of flights on UA metal. More flights overall to LAX and fewer senior UAL commuters... but more commuters from other airlines. If you received 737 out of Indoc you should consider LAS of all things, as it is shaping up to be junior to LAX and SFO. Plus, the commute is shorter/easier than SFO without very many commuters (but not as many flights to pick from). Have a look at a website like Flightstats to get a gander at how many flights per day to each location.