So do you guys have any strategies with the drugs? A lab with the new price is way outside of my budget atm so will have to rely on the basic ones for now.
Elixirs:
A lab allows you to brew healing balm (6$ plus however you value fiend mucus), which can make medical treatment less expensive. Once you can win battles at the border of the Fogs regularly, the cost of the lab can be offset by the sparks you get from disposing of the "rescued" slaves in various ways (including dropping them off with Farid, putting them in your barn as a pig, or keeping them to train [short-term or long-term] and then sell).
This income route is assisted by a dungeon, if you are not using your dungeon as an overnight punishment for a guilty slave. A disobedient slave can be kept in your dungeon to passively build fear (and despair), shortening the disobedient phase. (You can also use a slave in the dungeon as an example of punishment for your current slave, up to and including executing the prisoner to impress upon your slave how easily the same could happen to them, which can increase obedience.)
A lab allows you to brew Philtre elixirs (6$ plus however you value fiend mucus and requiring an S+ skilled alchemist), which apply a one-time increase to a slave's devotion. This can be combined with the high-level mage spell Domini Dictum to force a disobedient slave to drink it, even on day 1, to shorten the disobedient phase. Once the slave reaches D- (or higher), they can be sold to the guild subpurchaser, who only cares about rating, or to other buyers if you put in the effort to make them marketable. Alternatively you can use a Philtre to raise devotion faster between C+ and B-, B- and B+, A- and A+, or S- to S+.
Other elixirs can make combat easier and accelerate training in various ways. Overall, the lab pays for itself through cost and time savings if you use it effectively. You can optimize the expense by cancelling the lab rental after stocking up on enough elixirs to keep you supplied for a while.
Raw drugs:
Datura can slowly drain intellect if taken regularly. Kamra reduces energy and mood in addicts, so it stops providing a benefit and becomes a dependency that must be met to avoid a penalty. Oblivion, alcohol and pollen improve mood, mood and energy respectively, but can drain endurance for a long time after the slave stops taking the drug. Repeating a dose of oblivion, alcohol or pollen on the same day has adverse effects. The effect of repeated alcohol is less adverse and can occasionally be useful.
Recovery begins immediately after the slave stops taking the drug, but the rate of recovery is on average slower than the rate of addiction. If you want to minimize long term effects, don't give the same drug too often. How often is often depends on the random number generator. If you see a slave craving a drug when you ask how they feel, they've developed an addiction and you should stop for a while if you intend to keep the slave long-term.
Edit: Also are we positive the slaver stat teaching skill is working correctly?
Type
master_tutor_rate into the console (the button to the left of the options menu button). It will display how many times you've personally taught a lesson. The threshold for D- is 50.