Just a sample of what I mean:
The Steel Tower - During the retreat of Imperial law and the warships that promoted it, anyone with the means could become a king. Whole worlds were enslaved and exploited by those with the ships and weapons at their disposal.
One legend from <insert name here> speaks of a Solomani mercenary turned pirate, who landed his 400t cruiser on a secluded hill top and proclaimed himself lord of all he could survey. With the support of his troops and ship's vehicles, he quickly subdued the nearby countryside, forcing the mostly agrarian colonists into servitude. His cruiser became a make shift fortress, a tower of steel. From his fortress, he made war against other settlements; enslaving whole villages, and raping the land of its treasures.
As the years went by and repairs were less frequent, the ship's systems fell into disrepair. Stone and wooden palisades were erected around the hull for added protection against the occassional uprising or upstart. Eventually, the mercenaries, now with extended families of their own from local women, grew tired of their captain's rule and over threw him. The captain's last dying act was to destroy the ship's controls and engineering plant, leaving them all stranded on this forgotten world.
But the hull remained, gutted of most its free metal, and was used by subsequent warlords over the next hundred years as a fortress and treasury.
The ship and it's treasures may still exist. Some clues:
- Rumors are that several groups from the highlands of <insert planet name here> speak a strange dialect, strong with Solomani influence.
- Ancient laser cannon of Solomani manufacture have recently been discovered in the royal armory of the <insert noble family here>. The family intends to sell the artifacts as curiosities to bolster their waining finances. The ancient weapons have been in the family's possession for nearly 400 years, taken as tribute long ago from their holdings on <insert planet name here>.
From here the adventure could include some maps, deckplans, some colorful NPC's, and all sorts of red herrings and plot lines for keeping the PC's on their toes as they investigate the legend.
OR maybe rewind several hundred years and the PC's are part of the mercenary crew subjugating the colonists.
OR fast forward several decades from that and the PC's are children of the crew, trying to foment rebellion against the mercenary captain.
OR maybe the legends weren't true at all and the mercenary captain was really a hero trying to protect the colony from the real threat, a group of interstellar slavers. At a critical moment, when his commitment to the people was tested, his crew mutinied and his only recourse was to destroy his ship to prevent it from being used as a slaver. It's up to the GM to decide how or if to pursue this storyline.
It may sound very D&D-ish but I don't see that as necessarily a bad thing. Given a basic storyline though, any GM can retool what he/she doesn't like and add where it seems necessary.