One problem with a relatively near future setting like the Icy Shores is humans don't have a long time to develop very divergent cultures. By divergent I'm talking barbarians. I have no problem playing doctor, scientist or bureaucrat but let's face it someone in the party has to do the fighting. A Marine will do all right but a barbarian really makes a statement about a party of adventurers. Barbarians and space travel are a crossover you just have to make happen.
A barbarian evokes atmosphere, much like a skeleton in a spacesuit.
Sadly interstellar missions are going to have a high basic technology. Losing technology or knowledge was never easy historically, despite what people believe about the 'Dark Ages'. It's even harder to lose knowledge when everyone has a flash drive.
Saying colonists lost their technological tools as they were forced to adopt to a new world is dangerously contrived. They don't have to colonize a planet that is too dangerous. They can stay in orbit and have weekend trips to try and get killed. Colonizing a lush garden world probably won't make people go native. Don't even think about a domed or asteroid colony regressing. That just leads to mass graves.
Here's my take on barbarians in the Icy Shores. Hopefully it's not too farfetched.
The colony mission to Peraspera did not like the looks of the world. It was Earth sized but had an atmosphere rich in sulphur compounds, nitrogen and carbon monoxide. They were preparing to go on to another world when Lalande 21185 began a series of prolonged eruptions. The resulting EM effects interfered and damaged the maneuver drives of several ships. Landing on Peraspera became a way to avoid radiation sickness and death.
The colonists discovered Peraspera had life, microscopic plant life performed photosynthesis and was beginning to produce oxygen. The colonists introduced genetically tailored plant life to accelerate the process. Atmosphere processors were also set up. The effort took nearly all the colonists' resources. The terraforming worked in part.
The low lands of the planet still had concentrations of carbon monoxide, dioxide and sulphur compounds that made the air unbreathable. Settlement was limited to mountains and large plateaus. Fortunately Peraspera was quite mountainous. Terran plants and animals were introduced and a fragile ecosystem set up.
The colonists had to forego many amenities of 22nd century life. All efforts were bent to sustaining a livable environment. Even the colony ships were cannibalized for resources. The colony was surviving when Earth developed FTL and sent a rescue mission.
The Terrans with the Tycheans established a starport and help stabilize the terraforming program. A starport was built to support shipping for the air works projects. Part of the starport facilities was a system to warn of solar eruptions or turbulent storms that could blow deadly gases onto the settled areas. Gas mining became a source of revenue and higher technology items began finding their way into the locals' hands.
The Sperans had learned to deal with life without many high tech advantages. Bows replaced guns in many areas. Blade weapons were used to settle disputes in many cases. Court systems and due process took too much effort. People fell back on dueling to settle disputes. Airships had replaced air/rafts. In many cases the locals stuck with the simple and local technologies they knew, rather than plunge themselves into debt to buy offworld wares.
The oxygen masks the colonists wore in case of poisonous storms had become decorated and adorned and a symbol of rank and family. It led many to believe they were savages. As Sperans found employment as mercenaries this view became widespread. Pirates shooting bows and wielding battle axes get talked about. The Sperans themselves cultivated this mystique though they are not fools and will se a rifle when it serves them better.
Some personal high tech items that do not require much infra-structure or support are used by the natives: filter masks, flashlights, and personal communicators (simple ones that could merely sound a warning of bad air storms or solar flares from the starport) were all too valuable to lose. Oxygen crystals became vital to survival. Everyone wore one of the reddish crystals around their necks. In case of bad air the crystals would turn black warning their wearers.
Similarly a radiation counter was universally worn to warn of solar flares. The counters also became decorated and fashion items.
The average Speran who worked outdoors wore armor, a simple mesh made of bioengineered plant fibers or jack. These suits were often made by the wearer and to fit that individual. The handmade, one of a kind gear and and
clothing were amazing to people used to mass produced products. All this contributed to the 'savage demeanor' of the Sperans who encouraged it while quietly learning to operate computers and laser rifles.
Peraspera (Lalande 21185) M2V B7A2663-5
Atmo mix: N2, SFl6, CO with some SFl4. This results in the lowest regions getting occasional drizzles of H2SO4 and HFl acid resulting in a C atmosphere rating (if you get caught in the rain. Terraforming introduced O2 to the atmosphere allowing the higher altitudes to be breathable. Storms will occasionally kick some poisonous gases into the upper reaches so everyone carries an oxygen mask and there are shelters all over (type 7 tainted by sulphide compounds).
The highest regions are relatively safe. The air rates type 6. Poison storms from below are very infrequent. More likely a blow of SFl6 will require a breathing mask for a few minutes.
SFl6 is used in a variety of electronics and power cells. The starport supports a gas mining operation and shipping offworld. It also operates several satellites to tell the locals when Lalande 21185 emits a flare. Nice place to live.