Mine and Rhuell's favorite look with the Mongol Armor are the splinted leather greaves over mail (no spurs), mail gauntlets and fluted Varangian helm.
We also carry weapons with are relatively thin with comically large ends (Miaodao, Glaive). But that's just because it appeals to our sense of humor, so that's really up to you.
I found that the round cavalry shield looks good with it on your back, too, should you choose to ride as well (I just carry it for looks)
Here are images of the set