Depend on what is the units sub-story. Royal militaries have one structure, the resistance fighters have another. The rule of thumb could be just Private (Volunteer), Corporal -- the skilled private, Sergeant -- as a Squad commander, and Senior Sergeant (Sergeant Major) -- as officer's (Lieutenant) XO, or trainer for recruits, rest pretty much fillers. Officers only like 4 ranks: Lieutenant -- Platoon or special force Squad commander, or company XO to a Captain; Captain -- Company commander or special force Platoon commander as well as XO for Major; Major -- Battalion or special forces Company commander, and XO to a Colonel, or General; Colonel -- Regiment/Battle Group Commander, or for spec ops Battalion Commander, note that Colonels usually are not any XO's. Also, after the Colonel little bit murky, there ether Commanding Colonel, Senior Colonel, or Colonel-Commandant could in charge of the forces, or right away, Generals. In simple structure there usually ether one or two General ranks, where several Junior Generals and one Command. So, this is my take on army structure, furthermore, in a simple structure no such bird as Warrant Officer which is not in a chain of command rank, usually corresponds with some sort of specific skill/task. Also, the opinions might be varies, so somebody will offer something else.
Zibster,
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