" I have a slave at -1620 obedience from starvation, but they no longer lose obediance at the start of the new day." Clarify. This part sounds like you just hit a cap on something that probably isn't supposed to go outside the -100 to 100 range. It's probably natural that it stops decreasing at such a high number. Are you just saying Starvation doesn't work in general, of that it stops working obedience wise.
Because there are a number of moving parts that interact with obedience gains and losses to my understanding, and how they all interact is probably not been heavily examined yet. Like Natural recovery being stronger then starvation damage. I think it's just coded in without any real weighting or mulipliers considered for how things interact. It's entirely concieveable a slave might be too comfortable that obedience won't drop and starving doesn't bother them because they out heal the damage while sleeping. I also think ?fear? and obedience kinda lock out to some extent currently depending on which one maxes first, could be wrong. Starving them probably makes them afraid of you or disobeying you.
The Repeat Quest bit is probably right, as it's probably procedurally generated.
The talent bit buries the lead, you should edit it out.