I say Israelite to differentiate them from Israelis of today, I really don't know what the proper way of saying it is.
As for slingers and bowmen, I don't remember* any refernce to bows in the bible, nor slings (except for David and Goliath), but if you say they were a part of the ancient military, then I believe you.
Left Handed slings would be really cool, because I'm left handed
There shouldn't be a slinger hero? According to what you said, a slinger hero makes sense. We could even have David as a leader with powerful sling abilities.
Other hero ideas:
Cain Clone: If it was possible, making Cain Immortal and giving him the Blood Vengance effect would be really cool, this would simulate the Mark of Cain that ensures that he will: a) Forever roam the land b) Anyone who strikes him will be punished seven folds.
Elyahu/Elijah Clone: Uber prophet hero. This guy was a serious miracle worker, he even revived a dying child (Awwwww!)
Moses Clone: Another uber miracle worker, this guy can take credit (although obviously the credit goes to god) for a rain of frogs, turning water into blod, lice, complete darkness, a hail made from huge burning rocks of ice, etc.
Solomon Clone: Very wise, should be able to decrease chance of bad events happening.
Samson Clone: Uber strength.
*-I have a pretty lousy memory