Is Broken Crescent supposed to be really that hard? or did I just pick the wrong Faction...

I installed the MOD and started out a Campaign as the "Imamate of Oman" which seemed like an interesting choice.
I could hardly make any money, and before I knew it , 3 of the more powerful factions (Abbasid, Ayyubid, and Seljuk) all started a war against me. Even with early expansion taking over rebel settlements , they all ganged up on me and I was for 3 turns not even able to make any money (negative cash).
I tried to use standard M2TW building strategy of , Dirt Roads, Land Clearance, Town Guard, Market type building, Religious Building (mosque), and then military buildings for my Castles.

The other thing was that my faction was only able to make very very low level units, yet the "bad guys" already had Horse Archers and Heavy Armour Units and just tons of guys... And I was playing on M/M ..

Can anyone tell me some hints on BC, like maybe I am supposed to use different intial strategies or I am not supposed to keep much of a garrison (to get those units out in the field) ?