The Founder said: Those 3 options are the problem. Reducing your proposal to them does not make them less of a problem.



If you want internal Migration without danger of empire flight just allow migration, but do not sign Migration treaties (that asumes Migration treaties are even still a thing in 1.5, with the species rights rework). You literally have to do NOTHING to have that 1st Option.



If you want to have immigration from outside, you have to life with the danger of having emigration too. That is the price you pay for access to those additional populations. That is why a migration treaty does not cost influence.



What you propose is not removing Migration treaties, but turning them into a unilateral agreement you can just declare without any downside.





How would those Policies even interact?

What if you want the pops (allow Imigration), but thier current empire is not willing to part with them (Emigration disallowed)?

Would the Emigration disallow just have no effect?

Would the other side still have to allow Emigration, effectively meaning they still have to agree they can come to you? (That actually sounds exactly like what the Migration Treaty mechanic is doing already right now. So congrats for reinventing the wheel in your quest to never use the wheel again).



For Emigration only scenarios there IS Undesireables/Displacement already. Click to expand...

My first reaction to hearing this proposal was "it wouldn't be worth the extra clutter on the species rights screen." I think, though, you've convinced me that there are ways of preserving some of the features here without compicating the system too much.Setting a species citizenship to undesireable should by default prevent ALL immigration to your empire by that species, whether as migrants or as refugees. The undesireable status should be an option for all empires, except perhaps to xenophiles, even if no purge types are allowed.This gives most empires a degree of control over their population make-up without requiring them to be xenophobic or authoritarian. While in the early game you can simply choose not to have a migration treaty with a certain empire, later you find species migrating to you anyway by first migrating to an empire you have a migration treaty with. This closes that loophole. I've argued in the past that displacement should be more widely available for the same reason, for some manner of control over the population make-up in non-xenophile empires, but this seems like a better solution imo. If you combine this with population controls and other discriminatory practices it could eventually lead to the self displacement of a species by its own free will.Likewise, internal only migration isn't a bad idea, but it could simply be an option within migration controls itself (Allowed, Internal Only, or Banned). What you seem to be forgetting is that migration controls are at the species level now. If you want species A to be able to emigrate but species B to stay put, you can do that with the current setup, this just allows you to let species B migrate to your own planets too. You can't simply cancel your migration treaties because that would affect species A as well.With these two changes, you basically have the same controls that are proposed here, aside from the case where a species can get in but can't get out, which I agree is silly.