Au Ra physiology and other lore.

[jomoru]

So a steep is a grass plain like what the Apache and Mongolians lived in.

This still would permit the genetic speed vs power scenario since a smaller build is much quieter for stalking prey (and easier to conceal).

While the more physically endowed males would likely be the frontal force to bring large game down the females smaller frame would be better for stalking and tracking since they'd make less noise.

The females under that logic would also be ideal for stealth operations since, again, being smaller makes it much easier to hide and stay quiet.

Well if we are going to use real world examples then well the males are kind of well crap for the steppe. The females have a more Mongolian/Native america build. And Steppe nomads in Eurasia generally were all about being small mobile killing machines vs big bruisers. They made significant use cavalry, there's a reason why you don't have people like the Rock as Jockeys.

So building on that I'd imagine Xaela males are more home bound protectors of camps. Excellent at defensive strategies being larger and having less need to move. The females are the attackers, archers and lancers using their mounts to easily make up for the male size difference.