Like PrestigeX, I really like the Bulgarian Brigands. Probably my favourite mercenaries. It's because of their ability to actually be capable of defend themselves to a certain extent in melee. These are also available right from the start.

Bulgarian Brigands

When it comes to faction recruitable units, my vote goes to the Desert Archers. They only need a fortress (population 4500 castle) to be recruited, and have long ranged missiles. They are also pretty cheap (390 florins to recruit, and 100 in upkeep). And they look really cool too!

Desert Archers

Quote Originally Posted by St.Jimmy
One last question. If I place crossbows behind my lines and tell em to fire will the fire over or shoot my own troops?
No worries, they will fire over your lines by a mile!