I always feel like a real goon when I lead off with a flaw, but in this case, the flaw is kind of the key to cracking this thing wide open. There's a great campaign you can run out of this book, but in order to do so you have to tackle the flaw head on. . . but you can't correct it, because the flaw is also at the heart of this hypothetical campaign. There's no alternative to simply doing the work.
The flaw is this - Travar: The Merchant City makes the Scourge feel shorter than it ever has before. Even Elven Nations gave it more heft, and there are several canon elves who went into the kaers as children and survived long enough to come out as elders. Travar is a predominantly human city, so a 400 year Scourge plus 100 years since the kaers started opening means that roughly 20 generations have passed in which the major merchant families have survived as distinct entities.
Let's all care about the disposition of the Shakespeare estate. That's how it feels when the book talks about the Dumojoren family. Oh, there were two legendary brothers, one of whom was caught outside of Travar when it decided to seal itself away, and now the lineage descended from that brother is back and wants to merge with the branch of the family descended from the brother who stayed in Travar? What about literally every other human in both locations? That's how populations work. According to ancestry.com, I am mostly British. Therefor, it is highly likely that I'm descended from every single person who was alive in Great Britain in the year 1522 who has a line of descendants that survived to the modern day (though, sadly, this rules out Shakespeare). If 25,000 people go into the fallout shelter, and 400 years later slightly fewer than 25,000 people come out, those survivors are all going to be cousins.
So right away, you've got all these plots that rely on continuous organizations putting a pause on their operations and then emerging centuries later relatively unchanged and picking up exactly where they left off. And that's rough. None of the merchant houses was founded after the Scourge, despite the post-apocalyptic power vacuum, despite the fact that 100 years is more than long enough for a small venture to blossom into a major enterprise, despite the fact that the pre-Scourge houses were merchants, i.e. people who made money by moving goods from one place to another, and thus were 400 years out of practice because of their enforced confinement in a single area.
It's a flaw. But the reason I think this flaw might be massaged into a great campaign is because one of the implications of the short Scourge is so ghastly that it could easily be spun off into satire, and the longer the Scourge, the ghastlier and more satirical it gets. It's unjust when you're talking about the estate of your grandfather, absurd when you're talking about the estate of William Shakespeare, and fascinatingly ludicrous when Shakespeare died in a fallout shelter following a global catastrophe.
One of the merchant families loaned people money to build their own kaers. On the understanding that they would be paid back, with interest, once the Scourge was over (in the form of valuable minerals mined during the Scourge), and if the kaer dwellers failed to meet the agreed-upon price, their descendants would become "indentured servants" to House Achura.
This is actually one of the adventures. A kaer is refusing to open up because they don't have the minerals (turns out digging out the floor of your underground bunker is a bad idea when the bunker is protecting you from creatures who know how to dig a hole) and the residents don't want to be dragged away to work for the descendants of the people who loaned their ancestors money (which never actually arrived because it was sent through monster-infested country at the last possible minute). How the fuck is this even enforceable? Obviously, Travar's courts are massively corrupt, but even so, this is only a hair's more legitimate than just sending in a mercenary army and enslaving random strangers.
This is something that could work as a post-apocalyptic story -"oh, right before the bombs dropped in WW3, the President of the United States sold Colorado to Citibank, and even though none of the financial systems from that period survived to the present day, one of the novitiate scribes found a copy of the deed in a pile of dusty old documents and long story short you owe them a million dollars, which we're choosing to interpret as 1000 ounces of gold (because, obviously, the dollar no longer exists), so enjoy working without pay for the next 40 years, let's hope you get it all paid off before you die so your kids don't inherit the debt."
It's a weird post-apocalyptic story, but its weirdness could make it fun. I'm a little hung up on the way it dovetails with the Thera plot ("our ancestors gave your ancestors the technology to survive the apocalypse, so we get to rule you now"). Thera is openly imperial and comes to take slaves, and they are met by the united armies of Barsaive. Travar is capitalist neo-imperial and comes with antediluvian contracts to enforce debt peonage, but the book has you playing as the enforcers of House Achura. If you were aware of the hypocrisy, you could wring a lot of good social commentary out of the parallelism, but this book does not seem to have that awareness.
The "climax" section of the "Legal Documents" adventure says "There is no clear answer," but that's not true. The answer is very clear - the contract is void. Everyone who was party to the contract has been dead for hundreds of years, and no reasonable legal system would enforce penalties after all that time. Sorry, House Achura, but your ancestors made a bad investment, write it off as a loss, just like you did for the full century where the kaer remained undiscovered. Trying to extract payment from these people is basically indistinguishable from banditry.
And I guess the counterargument would be that if it is intrinsically illegitimate to sign a contract on behalf of your great, great x 20 grandchildren, then why would House Achura have even loaned the money in the first place? Wouldn't they have preferred to keep it in a hole for hundreds of years until it had value in the post-apocalyptic world?
And my counter to that counter would be - yeah, capitalism on the cusp of the apocalypse sure is bizarre and reckless, someone should make a game about that.
Anyway, Travar: The Merchant City really could have used a bit more of the weight of ages, but if you grant it a mulligan on that flaw, it's a decent fantasy city, with colorful characters, unique traditions, and a healthy dose of both political intrigue and magical mysteries. Also, they choose their leaders with a tournament. It makes a little bit more sense than AD&D's Ierendi, because it's the merchant who finances and sponsors the winning team that becomes Magistrate (and thus most likely the winner has at least some organizational competence), but it's still really quaint. You can put your characters through a really cute adventure where they play fantasy sports (rules included) to get their employer a job.
Ukss Contribution: According to this book, prominent merchants will hire people to walk out in front of their entourages in order to push random pedestrians out of the way. It's probably less effective than just waiting in traffic, because the merchant has to toss a few coins to whoever they knock down, but apparently there's a lot of status involved in traveling like a complete dick. It's a very decadent custom, and I always appreciate fun new ways to slander the wealthy.