I have 98% to 100% continuously through 2.5 regions. I can tell you what I do.
I always start out with trying to sneak around places and sync shot some of the outer guys. Larger camps I find a way in and shut down the power generator before taking out the inner guys.
If I get spotted and engaged then I tell the AI fire at will and typically then open the rebel cells if they are available.
At times I sneak into camps and only kill guys I can't get around to grab what I am looking for and then sneak back out.
Hope that gives some idea of what it might be looking at.