Camel Archer 22
Chu-Ko-Nu 23
Impi 1
Keshik 20
Longbowman 10
Would love to downvote the Impi, but since I have not played with them nor against them in another humans hands, I'll recuse myself.
Downvote to Longbowman. Great unit, certainly top 5, but the terrain limitations hold it back.
Up to Keshik. Swim in promotions. Use them properly and you'll have the most promoted units you'll ever have. No need for barracks, no need for Heroic Epic, just build them as they are and watch the promotions roll in. Upgrade path isn't terrible as they turn into tanks and if you're a terrible player like I am, the game may last long enough to turn them into super Promo'd giant death robots. Fun.