It's always been a voyage of discovery with Star Trek, which means it was more about exploration and diplomacy than blowing things up. The adventures of the Federation and their dedicated officers have included several races other than humans, and there are so many throughout the universe that it's impossible to tell the story of every single one.
There are a few alien races in Star Trek that might have been intended solely for plot development or to help make the setting more immersive, but those few moments on screen were compelling enough to make the viewer want more lore, more history, and maybe even a more prominent role in a modern series. Here are a few of the alien races from the Star Trek universe that deserve more attention.
7 The Deltans
The Deltan race, represented in the first movie in the franchise by a character named Ilia, doesn't appear as part of Starfleet crews very often. Their near-supernatural powers of sexual attraction make it mandatory that they take a vow of celibacy before serving on a starship.
The script of Star Trek: The Motion Picture has an interesting history. It stands in for what would have been the fourth season of the original Star Trek television series, and also served as a template for the setting and how several characters in The Next Generation would look. That's partly why the Deltans share certain distinctive traits with the Betazoids, such as deep intuitive abilities and increased powers of physical persuasion.
6 The Children of the Horta
As for an interesting race, how about one that proves sentient life doesn't have to be carbon-based? In the TOS episode "Devil In The Dark," the Horta first appears as a malevolent force harassing a mining colony, but further study on the part of the science officer of the USS Enterprise discovers its secret.
The Horta is a silicone-based life form, one that is able to move through, eat, and even breathe rocks and other solid or toxic matter. When the Enterprise left the colony, the miners and baby Hortas were just getting started on what looked like a beautiful friendship, but viewers never heard about them again. It's high time audiences checked in on this species.
5 The Reman
Viewers heard a lot about the Romulan race as distant relatives of the Vulcans and one of Starfleet's sworn enemies, but not nearly as much about the Reman. They've only appeared in one movie that everyone wants to forget about and two episodes of Star Trek: Enterprise. But considering how close they are to some of the most dangerous villains in the franchise, there should be more for them to do.
The Reman are residents of the Romulan star system, and have been forced to work as slaves in the Romulan dilithium mines. According to some lore, they occasionally rebel and take over old or abandoned Romulan settlements. Perhaps if they wanted to join the Federation and be free of the Romulans, Starfleet would be willing to help them, which could be a plot point in a movie that people might actually want to see.
4 The Whale Singers
There's a lot of weird stuff out there in the galaxy that defies explanation, and this is the extent of information the viewer ever gets for the Whale Singers from Star Trek IV: The Voyage Home. This race is never even named, and their odd, faceless spacecraft is only ever referred to as "the probe."
After the humpback whales confirm that rumors of their extinction have been greatly exaggerated, the probe quietly returns to deep space from whence it came. Humanity was so grateful to be left alone that no further questions were asked. As the Star Trek universe continues to expand into the Delta Quadrant and beyond, however, how cool would it be to find the Whale Singers?
3 The Orions
These characters always seem to get shoved into a script as sex objects or background decor, so how about a real story to even out the negative attention? Modern Star Trek seems to have recognized that the Orions haven't been given any kind of history or backstory considering their screen time, and there are new characters that do more than gyrate to dramatic music.
The fact is, though, that the Orions are a race of adventurers, pirates, smugglers, and other exciting professions that are always fun characters in stories. The Orion Syndicate was the closest they ever came to a functioning government, but Discovery's storyline involving the Emerald Chain and Minister Osyraa gave some more depth to this race that audiences would love to see continue to evolve. There are a few male Orions — maybe fans can get a story about them, too?
2 The Jem'Hadar
One of the more aggressive and generally unpleasant races that were introduced to the Star Trek universe via Deep Space 9, the Jem'Hadar are from the Gamma Quadrant and represent the Dominion. Not as just another race, however, but as their genetically engineered shock troops. They are trained and bred to see the shape-shifting rulers of the Dominion as gods.
Originally designed as clones, the Jem'Haddar were later given more individual personalities, and by the time they appeared in the DS9 episode that was also named after them, each had individual traits. An interesting story about the Jem-Hadar could be one of freedom and rebellion.
1 The Organians
This alien race makes one appearance in the classic show in an episode called "Errand of Mercy." Captain Kirk and his crew have arrived at the planet of Organia, which isn't exactly primitive, but seems to be arrested in a state of cultural stagnation and looks similar to the Middle Ages of Earth.
This makes the population vulnerable to the marauding Klingons, who are on the verge of starting an intergalactic war, and the Enterprise is sent to intervene and secure Organia for its strategic importance. The Organians turn the tables on the less advanced races, however, and compared to their power that includes everyone. Could this race of pure energy be related to other powerful races in the Star Trek universe, like the Q? It would be interesting to find out.