Gotta say man, I really like the ideas here. The only thing I'd say is that these are things that we'd need to discuss with Crazy and Avejoey long-term, because what you're talking about is less a writing thing, and more a re-write the game/mod kinda thing. That's a conversation that we should perhaps have. Crazy and I have been tossing ideas back and forth about new jobs (including some you mention, and more), naming girls, girls having an actual legal status (Free>Slave>Domestic Animal>Object), a better functioning dungeon with more rooms and reasons for them, and all sorts of things we'd like to see if we're going to improve this as a mod. The original game was less than perfect, and definitely could have used some of the features you describe. Those are things I'm totally down with.
The thing is, unless we can get a team going on rewriting the game from the ground up (or at the very least, portions of it), we might need to stick with current frameworks and just add on, or alter. (I could be wrong here, maybe Crazy or Joey will come back and tell me that this isn't so difficult) If we can all get together and decide on a major rewrite or rework of things, I'm down to work with you on the writing.
Barring that, it's important to know what can and can't be done in the current framework, and I'm more than happy to get with you in chat (Maybe tomorrow? I'm off a couple days, but I have to crash soon, got work tonight) and we can hammer out the details with Crazy. Crazy and Joey (and whomever else might be interested in helping) are really the ones that have to deal with the coding, so they have to not only tell us what's possible in how to write a scene, but also sign off on new jobs, new additions, reworks, etc. To that end (just in case you want to start writing on some of the current jobs in the current system) you should know that there is a LOT already available, much of it not in complete use. You can differentiate scenes already by free, slave, job, date, time of year, skill level, trait, items (I know there's a way to do that, not sure what it is), player birthday, girl's birthday, holidays. You can include the names of other girls in other jobs, so the girls can interact, meaning you have the framework (at least for writers) to have multiple girls, and indeed, multiple jobs in one scene. There is some extent of tagging, so if you take a woman and she was married, that is remembered and can probably be used, and since there is a your daughter trait, you can have scenes specific to your daughter. (And if you're a real bastard, perhaps a trait that could be modified there when she's a slave or animal or some such, making scenes specific to daughters you acknowledge and are free, and those that.... aren't.)
Things that currently aren't there that Crazy and I have talked about include (but probably aren't limited to) renaming, tracking siblings for incest scenes/jobs, twins/triplets, the possibility of turning the girl into an "item" in game and giving her to another girl, or a gang, and then having scenes pop up for her specifically in that other girl's/gang's scenes, deciding your daughters fates when they hit of age (including naming, legal status, etc.) These would be great to have from a writing position, naturally, but aren't there yet in the framework.
So if you're wanting to get into writing on the current game, I'd totally get into it that way. In the meantime, we can discuss whether we want to keep adding to the current framework, which is pretty good (and I'm fine with that, Crazy's already on board for a Ponygirl job, with integration with both the farm and arena for pony races and mounted combat and stuff, and we're slowly talking over other jobs like Human Urinal and Furniture Girl, as those aren't exactly his thing), or if it'd be worth it to at least look into what it would take to lay out a proposed system and work on it from the ground up. Either way, it's a lot of writing, and I'm down for it. Hope to see you in chat sometime soon, and we can get into writing together, swap ideas and scenes and the like.