I like the traits locked to locked portraits, finding random ones on AIs, I kind of feel like would be jarring.
Though there are not enough portrait-locked traits to really do it yet, but there ought to
- be an option in empire creation "respect/ignore trait-phenotype requirements"
- A galaxy generation option "forbid/permit empires ignoring trait-phenotype requirements (ai+human/human permitted only)"
Invalid empires, even forced on, wouldn't spawn, humans in mp would be forced to edit their empire or start without the invalid traits if violating the rule.
It would probably be a bit of a pig to code, but that would allow you to have the best of both worlds, I think. And makes the system totally scalable into the future. We can get more flavourful phenotype-locked traits, and those that want them can void the locking system. And we need more galaxy customisation options tbh.