Eagle Warrior (Aztec) - 45
Hetairoi (Macedon/Alexander) – 31
Legion (Rome) - 39
Mamluk (Arabia) - 42
Pítati Archer (Nubia) - 45 (44 + 1) The best unique unit in the game, perfect synergy with Nubia's abilities, gives you an early advantage, which will last you through the eras. The Ranged line is excellent through at least the first 5 eras of the game. Having a sizable and active army of Pitati Archers early in the game means you will probably have numerous ranged units with double strike in the coming eras, ensuring military dominance past the point where the outcome of the game has usually been decided. This is in part because of the synergy with Nubia's UA, which makes Pitati Archers less expensive and makes them gain more experience, but also because Pitati Archers can get to the action more quickly, and because their usefulness will compel you to build them in greater numbers.
Varu (India) - 4 (7 - 3) Good unit, but the weakest of the ones that remain. High production cost and low mobility hurts it.
War-Cart (Sumer) - 44
EDIT: Just a quick note on the general argument that naval units are worth less than land units...this is partially true, but consider that playing as Indonesia, you are likely to have much more use for naval units than most other civs, as you are more likely to settle coasts and islands, and more likely to be playing on a water map in the first place. As such, the Jong deserves its high position in the list. Boats are situational, but being Indonesia makes it far more likely that the situation will require boats.
For the same reason, the Viking Longship should have probably placed a bit higher than it did, in my opinion.
Also, it is interesting to note that as we get to the top spots, the earlier era units are dominant. None of the remaining units appear later than the Medieval Era, and I would not be surprised to see the that out of the top 3, 2 or maybe all 3 will be Ancient Era units. Arriving earlier gives a higher impact, as it helps you snowball. It also means that there is less unit variety on the map at the time, making the strong UUs harder to counter, and meaning that there are fewer production options competing for focus.
