Assign entrances/exits in Metro stations numbers or letters rather than street names.
Similar to what is done in the Shanghai Metro. In stations with multiple entrances, assign each exit 1, 2, 3 etc. These numbers or letters can then be put on maps within the station so riders can decide which exit to use. It also requires less signage and fewer words on all the station signs - which are already crowded and hard to understand. Announcements can also simplified, "Elevator at Dupont Circle exit 1 is out of service..."
And it makes giving directions easier, "Get off at Metro Center, and take Exit 3. Walk up two blocks..."