But, F. Xenophile + authoritarian does give 3 distinct advantages:
1) +20% trade multiplier for a per clerk output of 3.25 with thrifty and free traders, (as compared to a 2.75 output for thrifty slaves + free traders)
2) 95% discount on trade agreements, non agression pact, etc costs when combined with trait from diplomacy tradition tree (50% base)
3) It is much easier to get people to agree to trade agreements, non agression pact, etc than it would be as a xenophobe, given how valuable branch offices are, which require trade pact, this is a big advantage.
1) Remember that slaves are almost free to support unlike even stratified clerks? Since not all of your workers will be clerks, slaves are generally better, due to reduced upkeep and better housing/production.
2 + 3) If you go for Xenophobe, you don't involve much in diplomacy. You attack xenos to steal their pops, and when they are weak and meek, turn them subsidiaries. And you can build branch offices for no influence cost since it's free, i.e. no need for commercial agreement, with subjects.
F. Egalitarian + Xenophobe is great to use Utopian, but controlling your pops is mess, since you need to disable both resettlement (clearly a bug or oversight, since it shouldn't be applied to slave pops) and pop controls. You must follow bio path to convert pops efficiently to useful treats after every single war, or else things get messy. But with tons of influence habitats will be spamming almost overnight.
Militarist is great ethic for conquest, but it is of limited use for megacorp. Sure, fire rate is great, but you wouldn't claim much anyway, and fire rate alone can be compensated by stronger economy. If you go habitat route, your ship numbers will be huge thanks to stronghold/fortresses. Plus, Militarist is generally weak for influence generation.
Damn, if PDX fixed no-resettlement bug for slaves, this would be one of the best combos.
If you go Xenophile route, you get better trade to start with, but can't use slaves if you care about main faction happiness. And, as I mentioned, your pops are mess, especially with Xeno-Compatibility. Very hard to get proper pops in proper places, so calculations with BiS thrifty clerks are far from guarantied if you'd like to avoid micromanagement hell. And you can't reliably gen-mod your pops for best results, since they are too many and come constantly via migration from all over universe. If you want to go this route, Synths are very good, but they can't be Thrifty. But at least you'll get uniform nice pops. Well, theoretically you can use Indentured Servants as one of the picks, but dunno how effective it would be since never tried.
And for Xenophiles fanatical version rules supreme, saving tons of influence. So, Auto + F. Xphiles.
By mid-game you'd probably be one of the top dogs anyway, and can easily vassalize everyone, and it's rather hard to do to your fed members
