Played this last night for 120 turns or so as Tankhudids and it was pretty fun!
Archers are much better now, they decimate the unarmored troops but have major issues with armored enemies.
Also, plagues are far less frequent at the beginning of the game, but are still omnipresent later on (last 5 cities and 10 armies that I defeated were plagued). I propose to give AI 3 points of sanitation. I believe that around that number the plagues will still appear, but won't be impossible to cure for the AI as it is now.
There are a couple of faction specific issues I had (too much money as a horde, spearmans not balanced - same cost for T1 and T2, with T2 being much better).
Still, great experience so far, looking forward to trying some other faction in the future!