SO my concept is based on the dessert planet like Tatooine.
This planet is not even registered by the imperium register of planets. However, 10 years ago an Imperial Cruiser went off course due to faulty navigational information and intense radioactivity crashed landed. Killing 3rd of the men and 50% of the equipment damaged. Four of the 5 commissars and most leadership died as well, leaving Jr. Officers and Sergeants in charge. SO they started to set up a base of operations, motor pool, and fix what they could.
The interesting thing was they were shortly met by a scouting group of imperial rogue traders and other scallywags, black marketers, and bandits. This uncharted planet was secretly given to these folks (over a millennia ago) as a base of refuge, refueling, and exploration trading post. I think this information got lost??? The Main city is very exotic tech/ steam punk / wild west?? Lol
Sand storms can last for months at a time, solar radiation swarm all around the planet causing a disruption in all psychic navigational signals.
The ship is shot and no way will the Traders allow them to signal where they are for the fear of imperial meddling.
SO for some exotic goods, food, and fun the guardsman have been placed in charge of City and its surrounding security.
SO I want odd things as part of this guard army-
a- Squats ( I’ve seen them)
b- Beastmen unit
c- Hobbled together imperial vehicles
d- Fare out steam punk ish stuff.