Update 6/4: Metro is teasing their huge master plan for the 75-year-old Union Station and it's looking pretty blockbuster. Starting with the short term, according to The Source: First, the agency plans a $350-million track redesign that will cut down on transfers and wait time for Amtrak and Metrolink commuter trains. Next, Metro will ditch that ugly surface parking lot in front of the grand old station and replace it with a civic plaza that could include outdoor dining and an esplanade facing Alameda Street. The lovely old ticket room and Fred Harvey restaurant, now empty, could finally house new restaurants soon. Next up, Metro wants to move the Patsouras Transit Plaza—where numerous buses, including the Dodger Express, take off—from the rear of Union Station to the *west side of Union Station, but that will require that Metro acquire the nearby Mozaic apartments and tear them down.
Much of the impetus for the new plans is an expected increase in patronage; today's 70,000 daily riders could explode to 140,000 by 2040, assuming the high-speed rail line ever gets built. Should that happen, *California High-Speed Rail (not Metro!) will build a separate terminal for HSR behind Union Station, connecting it to the rest of the station with elevated pedestrian and bike bridges that will rise over the railyard.
A new grand concourse will take the opposite tack: it will *below the platforms where people board and exit Amtrak, Metrolink, and Gold Line trains (though by then, thanks to the Regional Connector, the Gold Line will likely be called the Blue Line and will travel from Long Beach to Azusa). (Update: The concourse will not be underground, as previously written.) The new subterranean concourse will be 30 feet wide, seven feet wider than the current one, and lined with shops and amenities. The entrance to the Red and Purple Lines will remain the same.
Metro also hopes to develop much of the fallow and underused land that surrounds Union Station. The rendering with the skyscrapers is just conceptual, but the agency hopes to develop about 3.25 million square feet of hotels, office space, and retail (no residential?) around the station.