I don't get the game after the last round of "adjustments". Early game is ridiculously tedious now, Isabelle lost all her obedience, leaving me with a useless accountant, guild pays me jack shit for contracts, what am I supposed to do except save scum low pride servant contracts to at least scrape by?
Assistant obedience is no longer fiat guaranteed, but Isabella still starts with high obedience and many useful skills and traits, and she can transfer some of her skills to other slaves. Calling her useless is a bit of a stretch.
Keep her mood up with appropriate clothing and occasional attention, and make sure she's aroused and the master is alluring if you're having her do something sexual.
Also use the dev version, if you aren't already.
Guild contracts aren't optimal for income. Save them for when you need the up-front prepayment to cover an end-of-decade bill or when you want to obtain a free high-quality slave without paying market rates (you can fulfill a contract with a different slave than the one they give you, so save the good quality ones for better things and fulfill contracts with others). Guild auctions also raise guild rep if you sell slaves rated above your current guild rank and pay more sparks than contracts do if you prepare the slave well.
To maximize guild contract income, you can turn in a contract on the same day you accept it. That implies you have a slave already trained before you pick up the contract. You can turn in an S+ rated slave for a D- guild contract and the payment will reflect the quality difference, but the speed bonus will be based on the D- contract. The highest guild contract payment you can get is with an S+ contract that you complete on the same day.
If you are already in the middle of a guild contract and you can afford to cover your cost of living for the time it will take to train the slave to a higher rating, it may be worthwhile for you to keep working on it, even if the contract will be late.
High nature is harder to train than high pride, because high nature opposes taming. Pride usually takes care of itself as training progresses. It's entirely possible to train slaves with above-average attributes from day 1 with zero points invested on extreme difficulty, so you don't need to be so picky about a slave's starting attributes.
Training servants is not necessarily the easiest (or cheapest) specialization. Smart slaves dislike menial labor, and stupid slaves learn slower. Assistant (secretary/elocution) is another two-skill specialization. Gladiatrix is a single skill but requires B+ nature and temperament, and a trained gladiatrix is more likely to fight back when punished. Art specialization skills have relatively low obedience thresholds, although there are three of them. Ditto for witchdoctor (nurse/alchemy/witchcraft). Etc. You will have more success if you tailor your approach to fit the slave, instead of treating them all the same.
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