Yeah the guy has got it: There needs to be more connections to other employment hubs other than downtown.

THe biggest and most important one to connect is the Santa Monica / Westwood area (where UCLA is). I think I read somewhere that the employment density is even higher there than in downtown. This area needs to get connected to both a rail line that goes downtown, but also a rail line that runs north into the valley.

One big reason we don't have this is that any rail line running north into the San Fernando Valley has to pass through Bel Air, and the rich people oppose anything being built around them, over them, or beneath them. Even if the underground rail lines won't affect them, they still oppose it.