The bat'leth hanging on the wall in the Paris-Torres quarters is not the black, angular version she received as a gift from the Klingons in Prophecy (2001).
The final line of the episode is Paris calling Janeway "Sir." In the very first episode she said "Despite Starfleet protocol, I don't like being addressed as Sir," and "Ma'am is acceptable in a crunch, but I prefer Captain."
Seven's flashback of the Borg cube is a reuse of a shot from the episode "Unimatrix Zero."