A good GM can improvise new situations on the fly. If you’re playing without a GM, and handing off much of the running of the adventure to a system of procedural tables, you risk losing this flexibility, no?
No! Here’s a rule that I’ve found can really help a group of players work together to create a flexible, open story, without a GM (and without things simply becoming a free-for-all):
If the group ever really wants to do something that the various random tables you’ve got access to don’t cater for, then you should go ahead and do it anyway! One way to male this fair is simply to invent rules for yourself – this is roleplaying, after all. But if you need a fair rule fast, just use this one: if there’s an entertaining and compelling narrative reason for it, you can gain any benefit, as long as you also suffer a detriment of equal point value.
When playing without a GM, any player can invoke this rule at any appropriate time.
The PCs are in an alchemist’s laboratory. The system tells you that there’s no worthwhile treasure in the laboratory – but one of the players really wants to take one of the alembics, because she feels she needs it for her own alchemical work. Time to Go Off The Rails! Simply declare that she takes the alembic.
Speaking roughly, that new piece of alchemical equipment is worth, say, 1 pt to her as a perk – so in order to balance this out, she will need to take on a new quirk, or quirk-level disadvantage. Perhaps she gets splashed with acid while dismantling the alembic, and now her scarred hand counts as a Distinctive Feature. Or perhaps successfully “borrowing” the alembic gives her a taste for thievery, and she acquires the “Light-Fingered” quirk. Or something else entirely – whatever seems like it will make for the most fun!
A second example:
The party has signed on to escort a shipment of goods, but half-way through the adventure they decide to steal the shipment instead. You could handle this by moving to a different kind of adventure – an Escape, say, as they try to make off with the goods. That would be a great solution, and the system I’m posting here supports it well. But if you preferred, you could also just declare that you’re Going Off The Rails, and say that the PCs gain $10,000 worth of goods, at the cost of acquiring an Enemy, negative Reputation, or the like, or equivalent value. You would then use the “Trading Points for Cash” rules to determine just how great an Enemy that shipment is worth….
The point is to keep the story moving forward in a fun and flexible way that allows improvisation, but doesn’t simply become a monty haul. I’ve found that mature players tend to do this fairly and reasonably, if given half a chance.