Eiffel and Cutter ostensibly have the same job, just at different levels. While Eiffel is the Communications Officer for the Hephaestus, Cutter is the Director of Communications for Goddard Futuristics.
Rachel, who once bragged about being an excellent judge of character, dies in the finale because she assumed Kepler would follow orders in support of the Bigger Picture. Instead he is able to quietly sabotage Cutter's plans from the inside and allows Eiffel to work unfettered when he could have caught him early on. She doesn't figure it out until Kepler has her away from the others and give her a Death by Irony, all because she didn't properly understand his stated motivation of protecting humanity.
The fourth season has an ongoing theme of characters exploring various death-related tropes.
Lovelace discovers that she is a doppelganger of the original Captain Lovelace, down to the memories and personality, and despite not believing she is really Captain Lovelace, she still sets out each day trying her bet to be the person Lovelace would be.
When Eiffel loses his memories, he listens to his old log tapes and wonders if he is still Doug Eiffel, or even if he wants to be, given the impression the tapes give of his old character.
Pryce, meanwhile, isn't given much screentime to ponder what her Death of Personality means for her, but now has a clean slate and a chance to start things anew with her surrogate daughter Hera, who she was previously very abusive of in her previous life.
Cutter, on the other hand, worked until his dying moments to forcibly reinvent humanity against their wills to make them his loyal servants.
Bob and the other Dear Listeners don't grok the concept of death, and don't understand the trauma they've caused by creating doppelgangers of human space explorers. Bob, under the constraints of the Psi-wave regulators, ends up being killed by Cutter, although Cutter allows for the possibility that he might come back to life.
Kepler and Rachel both end up facing their certain deaths in the same scene. While Rachel, dying of two gunshot wounds, is Defiant to the End and is Killed Mid-Sentence trying to belittle Kepler one last time, Kepler, shoved into a cycling airlock by Rachael, faces his Obi-Wan Moment by cheerfully downing a flask of scotch, because it'd be a shame to let it go to waste.
And then there is Jacobi, who seemingly goes out on a irreverent joke, but manages to survive because he's very good at what he does, and that happens to be setting very precise explosives and being a meticulous plotter.
On top of all of the Death Tropes listed above, it is worth noting that Eiffel shares a birthday with Jesus Christ and voluntarily suffers his Death of Personality to protect humanity. Further, he ended up stuck on Hephaestus to begin with because of his previous wrongdoings, while everyone else is there due to their own ambitions.
