If Jaya looks familiar, that's because she's played by Susanna Thompson, who later played the Borg Queen on #VOY as well as Dr. Lenara Kahn in "Rejoined" on #DS9.
This episode reminds me a bit of the movie Altered States, where drugs and sensory deprivation cause Williams Hurt's character to devolve into an early primate-hominid, but then turning into an "energy being" of some sort.
While I'm not a big fan of the Kazon on VOY, I did like the Trabe a little more (this was the main episode which featured the Trabe). Both were deceitful and highlighted Voyager's challenges in trying to find allies during their early years in the Delta Quadrant.
Tuvok tells Janeway about Spock advocating peace with the Klingons from "The Undiscovered Country". This was one of the few times VOY referenced TOS & TOS movie era. Another was "Flashback".