Out of curiosity: do you prefer high or low control and prosperity in your world? (I automatically assume everyone likes high corruption and low liberty, but correct me if I'm wrong)
Stand corrected.
About the liberty subject, I don´t care a fig about it. If freedom go over the roof, I would have trouble keeping slaves that are not convicts, isn´t it?. Well, a good chunk of my slaves ARE convicts, so no big deal. And if I must give freedom to some of them and keep them as servants, the only difference it´s that I can not assign a Slavemaster to him/her. As it will happen late in the game, my (former) slaves would be fully trained, so, again, no big deal. At all
An about the corruption matter, I don´t like high corruption. I don´t like low corruption either. Middle ground it´s what I like. Most of my slaves are in the 50-60 corruption score, and that´s quite fine for me.
About the subject of control, low control it´s something that you need in the first stages of the game. You need a lot of slaves to fill the ranks of Aria rebellion, and when your workshops are not at full speed the bandits are a big source of income. But latter, they are a pain in the ass. I don´t find interesting or any fun in going for 234th time to clean Stoke Hill of the Cellior Looters, so after overthrowing the government I strive for high control.
Prosperity? High, of course. I don´t see any drawback on it or any advantage in low prosperity.