The Doctor tells Paris that he's been named as Kes's replacement in Sickbay because it was determined that he has the most medical knowledge and experience. However, in season 1's Parallax,
Paris was already named the ship's medic. Although he never assumed those duties because Kes became The Doctor's assistant, the position was already officially his.
Janeway promotes Neelix to "official" Ambassador status with this episode.
You can see a boom mic reflected on the console behind B'Elanna when she discovers the bodies, near the end of the scene.