I think that a subway line down Beverly Blvd is imperative in the future to really allow people to live car free in "the city."
If you think about it, Beverly Blvd has tons of potential and is already a major thoroughfare.
It also slices Central LA right in half down the middle (where Wilshire Blvd. is the southern boundary and Sunset and Hollywood Blvds form the northern boundary).
If you think about it, you definitely need another east/west line down Beverly Blvd. from the Beverly Center all the way to the Vermont/Beverly Red Line station.
If you look at the map of the central city core, Beverly Blvd. really slices LA in half.
The line I drew is about 5 miles, which would make a subway down Beverly Blvd. about $1.8 billion (the price of LA Live!)