In the same way that the default D&D campaign was about plundering an underground complex, the default Traveller campaign was about a small starship trading from world to world and getting into trouble while it did so; and that seems like as good a spine as any to hang a Savage Worlds SF game on.
The Science Fiction Companion is easily understandable when it comes to ship construction and combat, less so for travel, trade and encounters. Let’s look at each of those in turn before we start rolling dice, shall we?
On first checking the rules for travel and upkeep in the Science Fiction Companion, it seemed it was always cheaper in the long run to burn extra fuel to arrive on the day of the hyperjump, because the cost of the crew’s wages is more than the cost of fuel. Experimentation showed this was wrong, for two reasons; first, you pay your crew once per month, but you have to replace fuel more often than that if you burn extra. Second, the cost of the extra fuel has to be less than the profit you expect to make on your cargo, or you will go broke within a few months. You’re likely to do that anyway, as you’ll see in the next section, although it takes longer if you don’t pay your crew.
It also seemed that the Knowledge (Astrogation) roll to make the hyperjump was dramatically uninteresting, because all failure does is delay the jump by a few minutes, and unless you’re being pursued by rakashan pirates or about to be eaten by a giant mutant star goat, it’s not worth rolling. Again, that’s not quite right; it matters how much you eventually succeed by, as raises on the astrogation roll reduce transit time and hence operating costs.
You need a good pilot to survive and prevail in combat, but you need a good astrogator to make a profit. Since presumably you want the astrogator to be better than the ship’s AI, he or she will likely have Scholar and the prerequisite d8 skill.
The intriguing thing about Savage Worlds trading (SFC p. 28) is that it has nothing to do with the characters or the planet they’re on. This makes it extremely portable; it’s a subset of rules with no connection to anything else at all.
After trying a few dozen trading voyages off-camera, I came to the conclusion that this also means that you go broke fast unless you have a number of possible destinations and know what the prices are going to be at at each one; if you don’t, on average luck over a long period you break even on the trading rolls, but it costs you money to move the ship around, so you make a loss overall.
Therefore, co-operation between trader ships is advantageous; they will share prices in some way. A government might operate subsidised ships of its own, or might pay for pricing information which it then shares on a Commodity Board at the starport, to encourage trade and thus boost its economy. A merchant’s guild might jealously guard the information, only sharing it between members. A large trading corporation might have the resources to do this itself, so the co-operation might be entirely internal to the organisation.
Whatever form the organisation takes, one of its primary functions is to collect price data from nearby worlds on a monthly basis (the prices change each month) and share them. This is limited to worlds within one jump of home, though, as by the time the typical ship has gone two jumps, collected local prices and returned, loaded up the best cargo and jumped back, the prices have changed, so there’s no point.
The organisation therefore has at least one ship per neighbouring world that basically does nothing but carry mail and news between the homeworld and its neighbours, and an extra one or two undergoing maintenance or repairs. These ships are as small as possible, since this minimises their operating costs on all fronts. Since there are ships (probably armed) scuttling around neighbouring systems on a regular basis, those systems count as "patrolled" for purposes of random encounters – see below for more on that.
Each ship trots out to an adjacent world at the beginning of the month, carrying something it hopes it can sell at a markup, then comes back. They share information, and then all make the most profitable run they can for the rest of the month; if there’s enough money to be made, the ships may burn extra fuel to reduce transit time, so that they can make more runs before the prices change.
Now, while it’s logical for these little ships to trade and thus offset their operating costs, they can’t be expected to make a profit, for the reasons stated above. So, like Traveller’s subsidised merchants, each ship has an Operating Cost Position – essentially, an amount the organisation will tolerate it losing. I reason this would cover fuel for daily operations and two hyperjumps per month (one out, one back), provisions, and crew salaries, but not additional hyperjumps or burning extra fuel to reduce transit time. Crews which lose less than their OCP are considered good; crews that consistently lose more than their OCP are replaced.
The SFC doesn’t cover these at all, although Savage Worlds itself calls for drawing a card if travelling through an area that isn’t patrolled. If one were using random encounters, the logical point at which to check is on arrival in a new system.
By the above reasoning, any world acting as a trade hub effectively patrols all its neighbouring worlds (those within one hyperspace jump), so there are no space encounters there.
Beyond that, hostile encounters are possible; my thinking is that in most cases the setting will tell you what PCs should encounter; raiders, over-zealous patrol ships, pirates and so on, according to where the GM has placed those; my instinct is that consistency in this will be more useful in the long run than creating complex tables. ("Let’s not go to Tortuga, we always get hit by pirates there.")
I can see I’m not going to want to track this in detail in the face to face game; while the characters spend a lot of time obsessing about trade goods and markets, the players neither need to nor should.
However, whether you call them scouts, couriers or trade pioneers, you could easily construct a campaign around one of the small price-checking starships, with the PCs as the crew. Start at the base world, visit one of its neighbours and have an adventure, come back and tell your patron what the prices are like there. If you make a profit, so much the better.