There are two human NPCs I have in mind for right at the very start of the game: Neil and Buzz (after Neil Armstrong and Buzz Aldrin). Both human NPCs would be wearing a full lab coat set. Neil and Buzz would introduce players to the logbook (bestiary).
As for other NPCs, well, I made three races: blue, red, and purple Eliatopians

The red guys look a bit like Chef Hatchet while the purple one was inspired by the old song "One-Eyed One-Horned Flying Purple People-Eater," hence its features.
Also, I made a new hairstyle for players and NPCs alike: the Karen haircut, also known as the "I Want to Speak to your Manager" haircut:

Figured it'd be funny to have that added into the game. But yeah, there's that.