One of the guys Marlo was based off, Marlow Bates, just got released from prison. (Marlo Stanfield character was a combination of Marlow Bates and his half brother Timmirror Stanfield)
The Wire has always been filled with symbolism. That can be a thread of it's own.
1:20
This is symbolic and foreshadowing of Carcetti.
He pours the last cup of coffee for himself and leaves the empty pot (until Kima called him out on it)