The staff of the United Earth Embassy on Vulcan is shown to be partially made of of Starfleet personnel, including what appears to be security. Unusual for a civilian or civil agency to do that.
They
look like Starfleet because the costume department re-used the same uniform, but actually their shoulder patches identified them as
United Earth Diplomatic Corps personnel, and their ranks included that of corporal, which Starfleet is not known to use (as opposed to the MACOs, for instance). Also, while Marines do of course provide security at U.S. embassies and consulates, other participants in play include the
Diplomatic Security Service, which is a civilian governmental agency.
The Horizon was J-class cargo hauler
Ah, this going by the theory that the Mayweather family's vessel from ENT was the ship from "A Piece Of The Action," which at first blush might seem to be supported by the set-dressers including as an in-joke a book about Chicago gangs on a bookshelf aboard the titular freighter in the episode "Horizon":
But it is not in fact the same book from "A Piece Of The Action," which was of different dimensions and had a different title (and yes, was indeed implied in dialogue to be the
original book left behind by that story's
Horizon, which was further said to be "from the same outfit" as the
Enterprise, which the ECS ship would not be):
Moreover, another piece of set dressing seen on DS9 was originally created to represent
that ship (posited to be of the
Daedalus class mentioned in context of another contemporaneous Starfleet ship in "Power Play" [TNG]) for the Okudas'
Star Trek Chronology:
WAR OF THE SET-DRESSERS!
