Well if you want to do an FF, it is the gold all the way. If you want to boom or turtle, it's the villagers. If you want to rush sending that may be useful, but I personally have no experience with it.
"I found no one ripe for many of my thoughts; the case of 'Zarathustra' proves that one can speak with the
utmost clearness, and yet not be heard by any one." - Friedrich Wilhelm Nietzsche
"The fearless are merely fearless. People who act in spite of their fear are truly brave."
Oprichniks are the best units in AoE3. Why? It's elementary, they're Horse-riding Russian Pirates, nothing beats Horse-riding Russian Pirates.