Ok if not using rewards to keep joy up we need something else..
Joy during training/breaking is another one of those juvenile concepts that came from game devs not knowing how else to handle it. It's a slave training, it is not supposed to be joyful or induce happiness under all normal circumstances (exceptions could be a use of drugs, some unique combo of traits or if we ever start tracking place of origin (previous circumstances), joy could be high if slavery is actually an improvement).
So, especially during the breaking faze, there shouldn't be a reliable way to keep the joy up except for some drugging system (we don't have one yet btw).
also need your detailed comment on (need approval) stuff for first and second post of this topic
It's good and saves me from typing out my concept in detail 
Traits for MC... Would have to be coded separately I think. Why can't we simply use combination of stats/levels. + In this case we can add training capability stat (will be a lot easier to code). Obviously unless we decide to implement MC traits system like one in Alkion... (another complication).
*Please note, I am not really opposed to having training related stats as long as they're isolated to the system (I call them flags, basically). New stats are expected to rise/fall during events, interactions, job and that's what is making them so difficult to balance out and keep track of. If a stat is limited to a system, it's not a big deal. I guess another thing is OW, Daisy spent a long time implementing per job stat/skill, took a long time and hardly felt like hardly an improvement to the game in the end.
Breaking/Obedience.It's good and prolly could turn out interesting. It's basic stuff so I don't really have anything to add/take away until there is more.
**My concept was to handle this bit differently (parts of it can still work with your system*):
- Congregate Breaking/Obedience into one.
- No obedience stat
- No reliable way to significantly lower true character (Unmodded by items)
- Traits/stats are slowly revealed on interaction/forced actions/time
- Purpose Multiplier (Tell a slave who/in what capacity she's being trained for. A girl trained to be a household keeper for wealthy nobleman should have a much lower multiplier than an all purpose slave to some peasant who got hand on some money for a purchase)
- "Breaking point" (Agreement/acceptance of situation) is calculated (based on stats + race + occupation + traits + maybe origin story (but latter is too similar to occupation to bother with in first version)) through one formula for any job and mitigated by pars supplied to that formula such as:
* Stats of MC
* Stats of all trainers and guards present
* Purpose Multiplier
* "Breaking flags" such as:
= Amount of days spent in imprisonment
= Amount of days in solitary
= Amount of days without food/water
= Amount of times beaten to several degrees
= Other
-(Flag based instead of stat driven)-
Before agreement/acceptance, any task is done either under great duress or refused. Past that, all tasks/training relevant to the purpose are performed without refusal unless she's exhausted/low on health.
Training faze:- Joy based responses (well managed personalized training = far better results)
- Stats/Traits are reveled fully the moment she agrees to be trained
- Huge penalties if asked to do training not relevant to occupation or told that she's gonna be sold to a completely different buyer (could fall back to breaking stage*)
- Sex with MC based on stats/requirement for sexual training. (unprofessional behavior from MCs part)
Selling faze:- Unless was required, customer should be put off by the fact that trainer slept with the slave (unrequested familiarity with trainer without good purpose)
- I've already wrote about options of finding clients
Other thoughts:- Some traits combination should make slave unbreakable (and time on them simply wasted):
My favorite quote from a Russian Adaptation of Greek play where a bitchy, shrewish female character frames MC for crime he didn't commit and he's convicted to be thrown off a cliff. His rich noble friend offers to buy him into slavery promising that it's just a way to circumvent the law (master choose punishment for their slaves so sentence by the court becomes irrelevant) and that he's never have to serve a day of his life to which he replies:
"So, where is the cliff for the free men?"
- There should be a registration for slaves granting them most basic rights and making sure that they understand that taking up arms/being trained in combat even if ordered by their master will result in their death (masters as well if actual order was given).
- No unregistered slave may be sold or be in service.
- Slaves should be a bit interactive:
* Ask for an audience with MC if they had enough of the dungeons
* Ask if they could do extra stuff if training goes well
* Ask to be sold to their master quicker if they like the prospect
* Ask to bed MC/Trainers if they so desire
* Plot/Plan escapes (also flag based)
- At some point I'd like an event where the registration authority would allow extra level of training in which a slave is given some cash and set free in the city for three or so day to see if she's trained well enough to come back, given the trainer an extra certificate. Result should be for a large part chance based, as most slaves harbor some hope of freedom (otherwise there wouldn't be any uprisings).
- Reusing labels (content), same texts/stat rewards/traits checks for sex acts (for example) during slave training, interactions and girlsmeets (main body I mean, setting is different in all cases obviously). Less work and should work fine.
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Prolly more, but that's all I can recall atm. If you want to use parts of this, feel free to add it to the concept.