And they have all one thing in common: they're fugly. Saying this as someone who suffers them regularly. Look at images of Moscow Metro stations to see a vastly superior alternative design.
Moscow metro is a work of art (the older stations anyway).
The only feelings that NY or DC metros ever evoked from me is "how fast can I get the hell out of there" and move on with my day.
The newest Silver Line in DC is okay. Being mostly open-air saves it.