Useless or redundant units?

[st.patrik]

I don't have answers for many of your points, but I think you're wrong about the Yavanas of Kailasa. With the right blessing these guys mop up in melee. The trick is just getting them into melee, which can be accomplished a few different ways, such as by having a screen of markatas in small groups out in front, and/or armoured Bandar warriors (which deal with arrows much better).

Try a water 9 blessing and screens of weaker troops to draw fire, and you'll be impressed with what the Yavanas can accomplish.