Words are weird. English words are weirder, thanks to that language’s status as an unashamed word thief. Military rank words, coming from even more different backgrounds, are arguably the weirdest yet. After some brainstorming, I’ve thought of a way where the rank structure we know could be flipped on its head. Even more so than, for lack of a better word, the “radical” rank system used by the SS and 1930s USSR, which involved variants of plain “unit leader”.
The lowest tier of personnel could be called “generals”, because they would make up the general population of the military. The highest tier could be called “privates”, because it would be a holdover from the time when leaders (openly) had private armies. May not be the most plausible, but it’s still an interesting worldbuilding exercise.