So what do people think that playing as a Muslim lord would be like?
I'm not an expert in the period, and hopefully some people here are. (And by 'expert' I don't mean, "I've played Mediaeval Total War!'
) But from what I know about the 'iqta system and Fatimid/Abbasid government, the main differences would be:
1. You can't inherit fiefs. You're appointed to them by the king and can be removed from them at his whim.
2. You don't control any troops. (Though the king can put you in charge of his own armies).
3. You aren't responsible for building improvements or infrastructure in your fiefs.
4. Polygamy means that dynastic marriages and succession work completely differently.
5. Plots and assassinations would work the same.
Now to my eyes that looks like it removes 80% of the game content, and would be completely unfun - unless you play at king level, in which case it would be much, much easier, since you control so much more under your direct power than any European monarch of the period did. But maybe I'm missing something?