Happiness level vs. brigands, revolts, etc?

[RedKnight]

In my experience, 100% is not totally safe - this the yellow smiley. One has to figure the cost of keeping standing armies vs. lowering taxes on a long term basis, then. In other words, it might be more economically productive to always keep cities in the green, if you have large areas with no border armies in easy reach. That's the point I've been concerned about. Comments?

[Quillan]

I haven't noticed any definite link between public order percentage and bandits. They seem to appear at random, regardless of your happiness rating. Riots happen at 70% and lower public order in my experience.

Revolts, however, seem to have some randomness to them. I suspect it's based on a ratio of the strength/numbers of the garrison to the amount of unhappy population. In my first campaign as the Julii, I finally got around to taking Cordoba away from Carthage, it was nearly 20,000 population, and I didn't exterminate (was still learning). Even with a full army there, at 70% public order I was kicked out. 30% of 20,000 is 6,000 unhappy residents, and I only had about 1,500 soldiers in the city. But a city of 2,000 with a 30% public order would riot but not revolt with the same garrison.