What beliefs did you choose for your religion? Constant WLTKD + theocratic rule + 3 religious buildings could potentially gain tons of happiness
To clarify, I took a look at happiness with no WLTKD, no GA, no WW or any other factors that would artificially increase/decrease happiness except for multiple puppets (unhappiness here and from my Great Admirals/vassal happiness would largely cancel out), and I had ~120 happiness and ~90 unhappiness, with my cities all set to default management working a moderate number of specialists. WLTKD brought unhappiness down to I think 75ish because of Hippodrome, Fealty, Synagogues and Theocratic Rule, but obviously at that point it was just overkill. But outside of WLTKD I was still doing very well on happiness
Religion was Ancestor Worship, Hero Worship, Orders, Synagogues, Zealotry, Theocratic Rule. So I pretty much erased unhappiness during WLTKD, but whenever it fell off I was still facing well over 100% happiness in a fairly wide empire that was also growing a lot due to consistent WLTKDs.
I'll planning on giving Progress/Statecraft Shoshone a try so I have a larger number of founded cities, no Artistry, and see how it feels. My experiences are reflective of how warmongering felt, and it looks like people are mostly having issues with either very-early Tradition and Progress.