One advantage to being downtown is that it's one of the better places for access via public transportation. So that opens up other options, such as living in Orange County and taking the Metrolink train into downtown, if you're willing to deal with an hour or more train ride each way (although that same drive would be longer). There's lots of good riding in central and south Orange County.
Speaking the South Bay - I have a friend who works in El Segundo (near LAX), but he hates the South Bay (too crowded for him and he couldn't get a house there), so he lives in Long Beach, near the university. That gives him the option of some good riding south down Pacific Coast Highway.
I live in Orange County (south of LA) and have a 20 minute reverse commute (to even further south) and great road riding out my front door (one block from Santiago Canyon). If my office moved to LA, personally I would prefer to change jobs and/or relocate to another part of the country, rather than dealing with either (1) a long commute from where I live now, or (2) moving closer to work but having to live in a more congested area.