Necro and some thought of my own, rather than starting a new thread:
- Animal people, gorlaks, and plump helmet men can be member of civilizations, but can also appear in the wild as "wild people".
- Gremlins are unique in that they're intelligent, but can be tamed and join your fortress, but still need constant retraining and you can't make clothes for them (and you can butcher and geld your citizens. They also aren't available for training after a fortress reclaim, so you'd probably end up with feral citizens). The UI doesn't allow you to assign professions to gremlins, but it works under the hood, so you can do it with Dwarf Therapist (where you can see their preferences, etc. as well).
- Ogres, trogs, trolls, etc. are slow learners that can be enslaved by goblins (although I've never encountered a goblin enslaved trog...).
- Plump helmet men are mute, by the way, so I believe the dividing line is the slow learner trait. Trogs are sapient, and thus cannot be butchered. Possibly, slow learners are unable to pick up the finer points of civilization (whatever those happen to be), but are still smart enough to understand the pain of a whip. If goblins keep their slaves in pens they don't have the problem with them smashing the furniture in the "civilized" goblin part of the dark fortress (and I wouldn't hold it for impossible that furniture smashing urges can be controlled the same way lever pulling urges can).
I'd like gremlins, the wild animal peoples group, and slow learners to fall into a common frame work with regards to fortress and civilization interaction, something along these lines:
- All sapient wild creatures caught in cages (and future versions thereof) ought to provide the victim with two options (plus "do nothing"):
- Request release: The trap is built at a location from which the map edge is reachable, a "release from cage" order is given, and the victim wanders off peacefully (you can of course attack it if you're the backstabbing kind). Escorting to the edge would be better, but probably more work to implement. It can be implemented even easier if you can just order the release, without building the cage first, but some creatures have irresistible destructive urges...
- Request visitor status: If granted, an order for the release of the victim is generated immediately, and the victim becomes a regular visitor who can then request upgrades to resident and then citizen status. If you elect to reject the request you can either grant release instead, or deny release altogether.
The options above are the ones theoretically available, but a member of a hostile animal people tribe wouldn't request anything (they're at war, and won't leave willingly), while slow learner individuals (probably the same state for the whole band, of a group) are either "at war" and won't request anything, or be "neutral" and request release, but not visitor status. It would be interesting if there was a small chance for a visitor request even from them, though...(provided any destructive urges can be kept in check). Hm, "The Cyclops Ubost the Bloody Cavern has come,..., to visit your library".
Also note that release might be problematic for cavern dwellers, since it's a common practice to block cavern access, with the cage traps they were initially caught in being the backup in case the drawbridges are down. Allowing them to leave above ground and then magically teleport back to the underground population as they leave the map might solve that, otherwise you might create exiled lonely miserable above ground individuals roaming the world... The same issue is present with cavern dwelling captives who have been granted visitor status.
In the same vein, I wouldn't mind having the option to expel captive enemies (after stripping them of their gear), in particular the nuisance kind (kobolds and snatchers, maybe even necromancers). This would be problematic with hostile animal people, though, since they currently seem to live in the cavern on embark, but if hostile animal people tribes would come and go like other "animals" expulsion would make more sense. It might also be possible to solve if the victim would be allowed to refuse.
I wouldn't mind if "wild people" could occasionally visit without being caught by traps by being tagged as friendly, and thus just walk right in, provided there is an open path.