I haven't done anything to my happiness and frankly I've found happiness to be far too easy this patch. I'm not paying any attention at all to what my cities are doing, they've grown uninhibited almost all game with nearly constant WLTKD in a fairly wide empire and 10ish of my cities have over 20 pop and close to 100% happiness, with a handful of ~15 pop puppets I'm looking to possibly annex. I'm working and getting quite a lot of specialists too. This is all in late industrial currently but since roughly medieval I've ignored happiness entirely with no issues. The one problem I have with the current unhappiness mechanic is that the "needs on growth" is often wrong, and sometimes by a lot. I'll have a city tell me it will get a bunch of unhappiness on growth only to get happier when it finally pops. It is pretty annoying that you either have to do a lot of manual math to figure out if growth is actually fine or not.