::District Overseer (Boss over Circuits - like Cardinals)
Mmmmm. Try Archbishop. You've been away too long, old friend--from mother Church, that is. :D
::Zone Overseers (I have never understood this poition, but I believe it is now part of the Branch)
The zone is comprised of several branches, generally geographically, and is thus under Executive--what used to be the old Office of the President. Recently Dave Sinclair of that office made a "zone trip" of seven weeks' duration, to inspect branches, facilities in--escapes me, Polynesia? South Seas? and report back. In past years a branch overseer might also serve other branches, in zone oversight.
Side note on "the Society."
I'm waiting for someone else to publish information on the new U.S. Branch operations that went into effect April 1, which left the old Service defunct--the result of the changes last October. I did see a post that had a URL scanning a letter from the Christian Congregation, with cutesie handwritten-type signature, modernizing the old Watchtower Society of New York (which was in NHKnorr's personal handwriting). (See below) The Watch Tower Bible & Tract Society of Pennsylvania rubber stamp was in the handwriting of Grant Suiter. The president of that Society is now Don Adams.
Musing: will future JWs refer to the Christian Congregation as we use the term "the Society"? That's a term that is decaying, for obvious reasons, although it's great shorthand for what we signify.
For most persons, "the Society" de facto is the Writing Correspondence Department, made up of some 10 brothers and 7 sisters. Cares for about 800 letters and 250 calls a month. You write in, they'll give you a database answer, whether Scriptural issue, Personal problem, Whatever.
For those who want to see the new "Society" at work, and the new kinder, friendlier and cutsie rubber stamp:
http://wis.i8.com/watchout.htm
Maximus