Like Kuauik says the Israelites will be split troop wise four ways:
Israelites = No cavalry, widest variety of infantry. Slingers, swordsmen (dedicated melee), spearmen, archers.
Aramaeans = Light infantry, light cavalry, probably going to get camel archers with the camel OSP.
Phoenicians = limited ranged troops, but very sturdy spearmen and probably the heaviest cavalry amongst the Israelite Faction
Philistines = Swordsmen with Javelins, and little else. Almost "Romanesque" in that regard.
We'll need to look into helping a player be able to do what you described, since I'd be worried how a player can revolt against King David and adopt an Aramaean/Phoenician/Philistine 'culture' with their new kingdom rather than simply take over the Israelite culture.
And on the topic of the Brewers that are he, Kuauik's latest top notch work:
Armor of the Gibborim and Israelite (probably some Phoenicians or Aramaeans too) noble NPCs.