So I've hit what I consider the mid-game of SS.
Cash is no longer a problem. I'll detail my path here for you.
You want to get both a Strategic Information mission and a Blind Bruiser mission somewhere in the mid to upper north of the Zee. If either one is at Polythreme, Cumaean Canal or Godfall, you're not going to make maximum profit doing it.
You're going to want 15 fuel and 10 supplies. (-250 echoes, some of which you'll already have.) You'll want to grab the Tomb Colonists and Recent News as well.
Head to Venderblight. Sell news and Tomb Colonists and get Port Report. (65 echoes.)
Zail north along the coast to Wither. Engage Lifebergs at your own risk. They're occasionally worth it IMO. Their loot seems like mid-tier with a small chance to be high-tier item. You get always get a Zee Story, at any rate. Get the port report from Wither. (20 Echoes)
Zail east to Codex, bypassing it and heading due east toward the Chapel of Lights. Get their port report (20 echoes).
From the Chapel of Lights zail East/South East toward Mount Palmerston and get the Port Report (40 echoes.) Buy more fuel at 9 echoes a piece (-90 echoes) and buy a handful of Eoliths for 35 a piece (-105 echoes.)
Now zail south to the Principles of Coral. When you hit them zail through them headed South/Southwest until you hit Port Cecil. (30 echoes for the port report.) You can occasionally find Colossal Flukes here.
Head west out of Port Cecil and hug the coral going south. You will eventually hit the Corsair's Forest. Bear South/Southeast until you hit Gaider's Mourn. Get the Port report. (30 echoes.)
Gaider's Mourn is a big
in profit. The Corsair frigates, when killed, drop between 1 and 3 fuel and supplies every time,
in addition to a medium quality loot drop. Hunting Corsair's alone can easily repay the entire trip. I can 2-3 shot them with Irons 103, and the tramp steamer. They will pretty much 2 shot me. Not the best strategy for hardcore players, but softcore players can have a field day.
When you're done hunting Corsairs, head south out of Gaider's Mourn and bear South/South East to the edge of the forest. Break out into open waters for a little bit headed south until you hit Khan's Heart. The port report there will get you 75 echoes (although it gets harder and harder to do.)
Then head to the light buoy at the very northwest corner of the Khanate, and go back the way you came. Sail west along the southern edge of the Corsair's Forest, kill another corsair or two, until you reach Station III (no port report but it has a ton of storylets and is a convenient stop along the route to save.)
From Station III, head west from the northern end of the island until you reach Abbey Rock. Grab their port report (20 echoes) but DO NOT DO THE STORYLET THERE IF IT'S AVAILBLE.
From Abbey Rock head west from the southern end of the island and hop over to Mutton Island. Cross your fingers and do the storylet there, and get the port report. (5 echoes.)
From there sail west until you hit the coast, and the back north to Fallen London.
Here's a spoil-y map:
http://imgur.com/pF5D9BQ In final release with shift map tiles, it won't always be so straight forward.
Totals
Fuel & Supplies (~ -200 - -340 echoes)
Strategic Info and Blind Bruiser Missions (+350 echoes)
Venderlbight (+10 echoes)
Venderblight goods (+55 echoes)
Wither (+20 echoes)
Chapel of Lights (+20 echoes)
Mount Palmerston (+40 echoes)
Port Cecil (+30 echoes)
Gaider's Mourn (+30 echoes)
Khanate (+75 echoes)
Abbey Rock (+20 echoes)
Mutton Island (+5 echoes)
That alone gets you a profit of ~+325 - +465 echoes. But those are just the fixed profits and costs. Along that route you can:
-Get a Judgment Egg from Mutton Island (Rare) that sells for +500 echoes.
-Kill a Colossal Fluke in the Principles of Coral and get a Colossal Fluke Core that sells for +500 echoes.
-Farm Corsairs at Gaider's Mourn to not only pay back your fuel and supplies cost, but get oodles of drops from them. (Everything from trade goods like Parabola Linen (on average between 40 and 60 echoes per) to Curiosities like Outlandish Artifacts (100 echoes) and more.
-Storylets from each island can always have a chance to be one of the monetarily profitable ones.
-Identifying the Eoliths you bought in Mt. Palmerston at the University will get you between a loss of ~100 echoes, or a profit of ~100 echoes, for 3.
Doing this circuit I always come out ahead. And sometimes, I come out way, way ahead. I've made as much as 2000 echoes from one run. I usually have a few more costs though. You pick up around 20 to 40 Terror depending on your route, so that's a couple hundred to pay down depending on Terror increases or decreases from storylets. I also use Torpedos to take down the biggest monsters and ships, and those run 50 echoes a pop. Still, it's very easy to be profitable.
Alexis has said they never envisioned the game as one of merchant trading. So trade goods are really not the way to focus on getting money. They supplement your income certainly, but rarely will they be the basis for it, even when more stuff is in. The real money is in port reports, storylets and monster drops in large numbers, and you simply won't find that stuff near Fallen London. So it's in your best interests to broaden your horizons as soon as its feasible.
If you absolutely must have an early game grind, you can make the run down to Mutton Island and take repeated shots at getting a Judgement Egg. It's highly random when you get it however, and you are taking a financial loss every run until you get one (-30 to -40 echoes per run.) But if you're playing softcore and save scumming, you can reload your save. Note, storylets seem to be generated the instant you hit port, before you can save. So once you reach port, the storylet you get is the one you're stuck with.
Hope that helps some folks.