In a way you did say that be cause you sayed he killed people and fought in a insurrection. By saying that you are saying anyone who did that should have warrior class
For gameplay purposes, the only characters who are warrior class are the ones with a shield icon. Currently, there is no way to "gain" warrior class.
For card design purposes, it's a little less clear. Some of the guidelines I know of are:
Was a soldier or commander in an earthly war, or had a position in or command of an army, even if there was not a war (which is why most OT Red and most Kings are WC)
Was a soldier or commander in a heavenly war (which is why Michael, Captain of the Host, and some of the Angel Wars angels and demons are WC)
Was a Salvation Army Promo that seemed like it would be cool as WC (Soldier of God)
Because we thought that certain characters would be way cooler as WC (The Strong Angel, Levi, Angel of His Presence)
The last two are more or less because (I assume) we wanted a variety of WC characters when it was introduced, and Levi just got lucky that the designers thought of him and Simeon's massacre as a reason for getting the class (though he is not considered to have fought in an earthly battle). So I would venture to guess for the future only the top two guidelines will be used.