Don’t railroad, flashback!

The below is part of a campaign/ blathery bit being developed for Adventurer.
Arc, Episode or Anthology
A primary decision to be made before running a campaign is the literary metaform. Specifically, and less pompously, are play sessions a story arc, an episode, or part of an anthology of stories on a topic?
The temptation is always to go for a story arc, with complex background and offstage consequences, elaborate histories and synthetic languages...but consider that most S&S is written as short stories or novellas at best. Robert E Howard wrote, as far as I can find, exactly one novel of Conan –all the rest are short stories. Interesting, most of the often derided pastiches and continuations by later authors, tend to be novels or expand into novels; and while the quality or verisimilitude of the stories is very much a matter of taste, I do think that they have a very different feel, lacking some of the sparseness, punch and speed of the original stories. (Of course, REH may just be a damned better author than most or many of them.)What this suggests is that the form of the story is relevant to the genre, and can possibly inform the play style of the campaign. I’d suggest that Adventurer, unlike Traveller and most of the myriad adventure sim games works best as an Anthology set in a specific world. I’ll elaborate.
As discussed earlier, an Arc campaign has a plot, a beginning and an end, and lots of things happen offstage. Conversely, lots of things also happen on stage, as part of the exposition. Travel, imprisonment, planning; all are generally played out. Further, it is almost invariably played in linear time –each game session happens after the last one, and the players (and characters) learn about the world in start to finish order.
An episodic campaign is very similar to the current sandbox definition. One has characters that are mostly consistent, in a world with the details, history and story very lightly sketched in. The story is written as it is played, and can veer off in very odd ways. In television, this is the classic sitcom – imagine MASH Frasier or Friends (or any soap opera) as a fantasy campaign –things happen in order, mostly, and the characters are the same ones, but who lives next door, or even what year they are in is unknown until it becomes important.

The next type (and these aren’t exhaustive) I like to consider is the anthology. Conan stories tend to be presented in a linear order, and the background is often very consistent; but the key is, they were written in whatever order the author thought of the stories. Specifically, there is a world that is more designed and planned than an episode/sandbox, but less than that of an Arc; many of the same characters show up in many of the stories, but not always the same ones. Original Star trek teetered between episode and anthology; a better example may be Gunsmoke or mission impossible. The play sessions have little effect on one another beyond the characters, but the world is fairly well defined. Additionally, and this is important, the actual episodes may jump back and forth across time, occasionally having very different characters –one can argue that the Hyboria corpus of REH is such a story structure including Conan, Kull, and IIRC, some later adventurers, if one reads it’s stories in the order written, not in the order they occur. Try it sometime; it’s very different from reading Conan from starting as a callow youth and ending up as a king.

So, what does this suggest for Adventurer? Simply this: AVOID arc structures. It telegraphs the plot and the events, and foreshadows the end –a big part of S&S for me is the twist and surprise, and the feeling of experiencing a foreign culture because you don't know the history inside-out.
Sandboxes, too are great, and can do S&S –except that it is hard to convey the effect of unearthly situations when there is no expected set of rules. In other words, why is a giant snake a big deal, and a mind numbing horror? Because it breaks the rules, and is impossible, incomprehensible, even sanity shattering !

So when one has a world where it isn't clear if there is a badger over the hill or a pair of clockwork Canadian Octopuses wearing tartan leather jockstraps and holding ray guns made out of cheese, one loses the essential sense of surprise and wonder (and horror) at encountering a dude with an elephants head in violation of all rational experience.
A good set of rules (not Tolkeinesque detail) about the world, a map at a high level, a few axioms (humans are everywhere, kingdoms are renaissance level , non-humans are only a rumor, silver is good, copper is common, gold is rare) all allow one to set up the campaign for surprises, without bogging down in detail, or jading the characters.
Finally, the freedom to skip around in the campaign is not to be dismissed. Screw up the characters with a deathtrap or an insane amount of wealth? Jump back to when they were all comrades in arms on the Whoknowswherian frontier for a good old punch up ; then come back with some new insights as to whether or not that was the last game. Maybe it is, and the rest is the early history of how they got there –or the story of just why it is that this mage had such a hate on for them in the past.
Plus, all DMs know that its always fun to actually pass on the detail and history that you have loch so cleverly and laboriously developed to the players, but hard to do it without pontificating (“ you see an old man, who starts taking at you, despite all your best efforts. He says ‘many centuries have my eyes seen of this temple, blah, blah, blah’ “) or have them ignore it:
"You find an ancient book"
"Is it a spell book?"
“No"
"Cool, I'll stick it in the mules pack until I can sell it"
fade out to sound of GM's teeth grinding

Instead, have them play out the centuries old events that left the anteroom full of skeleton parts. Hell, do it in the middle of the current adventure, right after they find the ‘Red Room of bronzed Femurs” and before they go on.
“As you open the door you have a vivid flash of memory of a story you heard as a terrified child one dark night". Break out the secondary characters, kids, cut story time.....

This suggests one way to prep for this is simply to have several characters per player - with the Adventurer generation format, this is quick and easy, and you don't have to tell the players why. In fact, if they have heard about the game, they'll likely assume that it's simply to have quick replacements when the current ones snuff it.

It’s difficult, but the anthology it really gets around the inertia that a linear campaign can often generate. Plus, linking two good story ideas is often the most painful and contrived part of any Arc style campaign planning. This way, you just dump them in it. The progression is somewhat linear but need not be. In fact, if one plays without experience rules, as per CT, this is very, very easy to accomplish. Players can cope with not having stuff that they will have later much better than having to lose skills they rely on. Otherwise, either bookkeeping, or willful suspension of disbelief is needed. Your call......