How do you sustain a blood econemy?

[AreaOfEffect]

When I first played this game I tried the first thing that comes to people when trying to decrease the unrest caused by blood hunting...patrolling. The problem I had with patrolling is that I often found myself devoting more and more resources toward unrest control. Not only that, but I also saw the population of my provinces start to die, even with high growth scales.

Recently I have come to think that a better approach is to simply drop the taxation of the hunting province to zero. I find that it has a profound ability to lower unrest. I have yet to create more unrest then I can handle with this strategy. The advantages and disadvantages in my assessment are as follows.

Disadvantages:
1) A total loss of income at the blood hunted province.

Advantages:
1) Population growth can occur as along as you have one level of growth. The biggest killer of population while blood hunting seems to be patrolling.
2) Commanders and troops are free to do more important things, or you could simply not hire the troops and save yourself the upkeep of the patrolling army.
3) You can't count all income at the province as lost as the unrest caused by blood hunting means that you always give up some money.

I wish I could think of more disadvantages, but I can't.

The best part about this method has to be the sustainability of it. The loss of income isn't permanent and can be restored in full once you decide that your commanders need to do something other then blood hunt. A high population province will remain high and even grow with just one level of growth. This is important as your slave income is affected by the total population.

Personally, I also like the thematic. The tax collectors collect your children instead of your money.

Pleases, tell me how you handle blood hunting. Maybe there is an even better way if we consider the options.