The house of Lt. Kitan's parents is the same filming location as the parental house of Johnny Rico from the movie Starship Troopers (1997). Incidentally, both sets of parents disagree with their child's choice to join the galactic fleet.
The home planet (Xelayah) is pronounced exactly like the name of the place where Spock undergoes Fal-tor-pan (The Refusion) at the end of Star Trek III: The Search for Spock (1984) - Mount Seleya.
Ildis tells Captain Mercer they've far superior doctors on the planet than on the Union ship. Likely a nod to the fact that guest stars Robert Picardo and John Billingsley, both played doctors on past Star Trek shows: Picardo on Star Trek: Voyager (1995), and Billingsley, Star Trek: Enterprise (2001).
Patrick Warburton (Lieutenant Tharl) is a frequent collaborator in Seth MacFarlane's other project Family Guy (1999) as well as Ted (2012) and Ted 2 (2015).
Alara's sister Solana stands out as the only blonde among a family of dark-haired individuals. Halston Sage (Alara) is a natural blonde and wore a dark wig for the role.