The palette
Water is the great mass here, and there is a lot of it: harbour, basin and bay share a single ink. Take it deep enough for the piers to stand out in negative along the harbour edge. Green is the second voice, and on this map it is in the data: the Common, the Fens, the river parks and Franklin Park all take the same tint. Choose one that stays clearly apart from the water, because the two touch all along the Fens. Everything else is line work, and the contrast between the tangle and the ruled blocks is carried by the streets alone, whatever colour you give them.