so you could say that she’s an arms dealer.

Most of the stuff I know about ranks is from this book:

http://www.wowhead.com/object=191642/the-death-knights-of-acherus

and its successor:

http://www.wowhead.com/object=191645

I gave Tev the rank of ‘Scourge Commander` pre-Light’s Hope, which I felt was basically the equivalent of Colonel. It got prettied up and changed to “Dread Commander” (like Dread Commander Thalanor) when they let the Scourge. It seemed like a fairly prestigious rank even if he lost a bunch of power when becoming a free agent, and it meant that Koltira was his commanding officer.