The title may be a reference to the Aristotelian concept of the common good, although that has been used to justify utilitarian positions, where the correct decision is deemed to be one that benefits the greatest number of members of a given community. Of course, that means that the minority may bear the brunt of the disadvantages.
The synopsis of the episode confirms the spelling of Elborean and Delmonda.
McGivers’ log says it’s the 208th day of the exile, which means about a month has elapsed since the last episode.
Delmonda says a “pandem” is “a collection of minds bonded beyond convenience or aptitude”. Given the literary proximity of Khan’s story to Milton’s Paradise Lost, one can’t help but think of “pandemonium”, which was Milton’s name for Hell, or “the place of all demons” (pan + demon).
The deception that Delmonda detects from Khan is of course his spin on how he came to Ceti Alpha V - not by choice, but because Kirk exiled them there.
Joachim calls the Elboreans “Elbs”. Erica says he’s the best fisherman of their group and the first one to chart the “Sunless Sea”, taking the name from McGivers’ quoting of the opening of Coleridge’s “Kubla Khan”: “Where Alph, the sacred river, ran / Through caverns measureless to man / Down to a sunless sea.”
Ursula says her and Madot’s baby is due in eight more weeks (two months), which is consistent with it being about seven months since the start of the exile, since the baby was conceived about a week into the exile (KHA: “Paradise”).
Khan says the four most terrifying words in the English language are, “We come in peace.” In DIS: “The Vulcan Hello”, T’Kuvma exhorts his people to “lock arms against those [the Federation] whose fatal greeting is… ‘We come in peace.’”
McGivers alludes to the fairy tale of “Hansel and Gretel” when she says “no wandering through the caverns without breadcrumbs”.
As noted at the start of “Paradise”, in 2287 (six years prior to 2293) an “anonymous source” (or so she told the Starfleet Civilian Resource Allocation Committee) gave Lear McGivers’ logs recorded while on Ceti Alpha V. She now reveals that it was Delmonda.