Now that each pop will only have a single, non-fanatic ethic in 1.5, how will the ethics be rebalanced? I think that either the empire-wide modifiers for having a particular ethic should increase fairly significantly to compensate for the overall reduction in pop homogeneity. Essentially, the pop modifier of each ethic will, without any other changes, be worth 66% less than it is now.
For many ethics, the Empire effect was already rather strong/the pop effect negligible. Or the pop effect ended up being too strong/important to ever loose it or use it.
The Militarist bonus to wartime happiness is nice and all*. But the +10% Weapons damage actually stays with you.
Collectivst was one where you only wanted the basic version - for the Slavery Tollerancy and the Techs. Supressing factions only realy helps with extremely large malcontent slaves as the cost is capped.
From Spiritualist you wanted the Empire effect.
Xenophobe? Empire Effect on borders and buildings. Maybe Xeno Slavery, but not stable enough to use longterm.
Xenophile? Should be turned into more of a Empire/1.5 Faction effect anyway. Way to micro-managy as it is.
Pacfist? The Fantic Bonus/penalty went way overboard.
Collectivist, Materialist, Individualist, Pacifist are the only ones where the pop effect actually matered. And likely much more then the Empire effect. However they did still have buildings to carry those bonuses over to lategame when divergence had removed them (Stock Exchange, Research Center, Paradise Dome) or to counter divergence (Collectivist tech).
And with pacifist there was a decent case to actually wanting to get rid of it eventually if you want to go to war later, with all the Pacifist bonus to buildup.
*at least early game with not much divergence having taken place, it effectively negates wartime faction activity. But that is lost on Conquest or divergence.
What I think this rework will focus on most, is removing absue potential. Like building up under pacifism, only to then go to war and maintaining pacifism (and all the buildings it unlocked).
Since every ethos will have anti-divergence if you just "act according to it", that means the Individualist needed for reduced Polciy happiness can be removed. Wich will also remove the entire Individualist Meta.
It will also finally solve the issues that Ethoses that did not stack Ethics divergence or anti-policy happiness were not competitive.
Many of the stock factions were seriously flawed under the current ruleset:
UNS Individualism countered maximised use of it's Xenophilia.
Commonwealth was okay to prevent pops from diverging up to a certain size (Symbol of Purity + VC-Arena). But what about converting conquered pops? Or if you expanded too much?
Ix'Idars extreme faction supression only mattered for Salvery. But slavery can not be used for Science (Materialist), not even via Energy.
Chinorrs Individualism defeats the Materialism long run.
Jehetma had issues winning the game even via federation warfare. Not to mention that Happiness builds and slavery do not mix anyway and that Fan Pacifist will backfire even with Liberation wars.