I've put together a giant spreadsheet to determine how the math works out for ACKS' hijinks system over the last couple of days. We had some issues with hijinks in the campaign. First, the bard took over a town and accompanying thieves' guild, and turned the guild into a secret police force of unparalleled size and profitability. At one point, it was earning enough money per month that I seriously considered having it count as taxes for the purposes of domain morale (and it would have had a reasonable negative effect). The PC response was to expand the domain to dilute the taxation across a larger population and mitigate its impact on morale. Later, the party wizard caught on to the fact that spying was ludicrously profitable, hired himself some thief henchmen, and sent them spying in a nearby town, thereby avoiding the associated morale complications. Again, great profits ensued, and he rapidly levelled past the party's other wizard, who had previously been several levels ahead. The extreme profitability of hijinks engendered much resentment in the PCs running normal domains, and helped lead to my proposal for guild morale, as well as the end of the campaign.
my interest in taking a look under the hood, so to speak, and determine
if the problem lay solely in permitting non-thieves to run syndicates,
or if it ran deeper. The trouble is that it stands to reason; just as
anyone can logically hire an engineer to build them a fortress and then
hire a garrison to impose their will on the peasants, it also seems
reasonable for, say, a wizard to hire a gang of thieves to steal monster
parts and spells from his rivals, and to sponsor the construction of a
hideout for them. But the numbers... the numbers are interesting.
They were so interesting I wrote a really long post draft about them, then realized that they honestly weren't that interesting.
The main takeaway for me was that the numbers on the Monthly Hijink Income table are clearly based on different assumptions regarding the costs of punishments and legal defense. What I'm seeing is significantly higher than the numbers on page 141. Other highlights included "hiring a lawyer +3 pays for itself in expectation", "treasure hunting is absolutely the best, followed by spying, followed by stealing luxury goods at -4", and "asymptotically, income scales slightly super-linearly, punishment costs drop to constant, and wages grow exponentially, making it inefficient to employ thieves of 9th or higher levels."
But honestly, after staring at numbers for many hours and thinking about things, I think I've reached a conclusive house rule which is probably in the spirit of the original rules. It's important to have these things written down, though. I'm fairly happy with it on first inspection, as it creates a nice parallel to the wizard and cleric domain stuff and limits the potential for hijink abuse which did so much damage to my last campaign.
Thieves, assassins, nightblades, venturers, and whatnot of 4th and lower levels may perform hijinks only as part of a guild. They do not keep the earnings for these operations, and gain half the GP value as XP. They lack the contacts to effectively profit from their skills when operating alone. They may still perform long-form skill checks for specific narrative or intelligence purposes; if the party wants to hire a Ruffian (Spy) to go to court and spy on the duke, they can do so. However, without a network of criminal contacts, the ability to make a direct, monetary profit from what is learned or stolen in these operations without performing further adventure-type activities is limited to effectively nil.
Hijink classes gain, at 5th level, the ability to perform hijinks personally. At this point, they have the experience to operate independently, and have a network of small-time fences and such who can get them cash for relatively small quantities of goods, but whose trust extends only to the character himself and not his associates. It is at this level that guildthieves are considered for positions of authority in the guild, while those passed over often 'go freelance' before fleeing town. However, while competent, the thief lacks the experience and wisdom necessary to train others. This mirrors the ability of spellcasters to perform magic research and create minor magic items at 5th level, and the 5th level fighter bonus to hireling morale, both of which enable 'early domain / wilderness play.' While the wizard and cleric can start making magical preparations for wilderness adventures and researching their own spells, and the fighter can now lead mercenaries with greater ability, the thief becomes able to provide maps and funding for expeditions by illicit means. This gives thieves something to do while other classes are performing long-duration early-domain actions like research, but makes it effectively impossible for the players to directly hire thieves capable of performing high-value capers. Thief henchmen of 5th level may, however, perform hijinks for the benefit of their employers, just as cleric henchmen of 5th level can make potions. Henchmen do have to get there by either adventuring or guild work, though... This inability to manage sub-thieves except as henchmen also puts the threat of punishment squarely on the head of a PC or his close allies for a while, rather than on "Anonymous Spy #12" as we saw previously. That hijink income is now much more limited also brings it back into the realm of comparability to trade income, which makes the latter significantly more appealing, and hence traveling wilderness adventures in order to accomplish it rather than sitting in town waiting for the monthly guild finance report.
At 9th level, the thief's skill is legendary, and he is a master of his craft. He attracts followers, can establish a hideout, and all the normal 9th-level whatnot. Additionally, the thief's ruffian hirelings of 4th level and below may perform hijinks for profit and XP, as he now has an extensive network of fences and information dealers of effectively unlimited capacity and he can offer them effective intelligence and guidance won through hard experience. The cost of establishing a hideout is then explicable not only as the construction of front operations and secret tunnels, but the importation or employment of fences sufficient to move large volumes of stolen goods and the acquisition of supplies necessary for training new guild members. This 9th level ability to train mirrors the ability of wizards to gain apprentices.
This is all I have to say on how hijinks should work. It is probably pretty obvious, but we were running under a very, ah, loose interpretation of the rules as written previously. More fools we; so it goes.