I keep meaning to reply to this and forgetting. While I do like your redo of the ranks generally, one thing that BIS Operations won't have is 'captain' as a substantive rank, only as a positional title (too many arguments in-setting). I do plan to post a new version using ideas from your post when I'm less tired, though.
EDIT: Also, I feel the need to point out that modern military forces can each have two types of Colonel, three or more kinds of General or Admiral, three or more kinds of Sergeant or Petty Officer, and some navies have several kinds of Captain (e.g. the
German Navy).