A nice reconstruction of the Abbasid military. What will tier2/tier3 be based on? I can see some Mamluk helmets in the early roster so I guess tier2/tier3 Ghulam class will be based on Mamluks too, the rest of the roster can reflect native military elements of the region, with Turkoman and Kurdish auxiliaries/mercenaries.
I also look forward to seeing trebuchets, not necessarily animations though, some screenshots of the 3D model would be good.