Playing the new patch as Spain (I want to keep pushing on the high early growth to see how the system handles it). As of Turn 136, happiness is in what I consider a solid place.
I have 7 cities and I've had to pay the happiness piper, but in a good way. The thing is that the Global Penalty hurts, but it REALLY hurts when you lay that on top of local penalties. Its quite easy to have a -45% growth, and -30% military production, and at that point in the game that is hard to ignore.
Funny enough I am finding the new system simplier yet more engaging at the same time. There are two levers now, Global and Local, but I find them very concrete and easy to understand. In some ways Global is my expansion indicator, if I can get it high enough I get to expand again (at least as Spain where I want to go wide).
Meanwhile, I play the local city minigame. Right now for example I have 80% global happiness, but I have a few cities that have a -2 or -3 unhappiness which I am trying to address. So I can feel "good" about my happiness overall, but still not ignore it.