I have a sloppy impression that things in this area have improved since the base game was released, but there are still some very weird behaviors from the occasional major and the incomprehensible business of minors building influence bases.

In my current game, the Korath have been being properly warlike by trying to build an array of war bases on their frontier and the Yor have been building (less than ideally located) influence bases to try pushing back my encroachment on their border. But the Carinoids and the Akilians have both built several influence bases right near their worlds, which makes no sense because they can neither flip a world nor have their homeworld flipped.

And that's weird, too. Why would Yor bother with influence at all when they have their loyality all up? And (depending on the version you play) they do lack Yellow-techs as well a lot; and/or with strong soldiering/miniaturization the course of action is clear right off the start.

It's not really weird. Foreign ships in their zone of influence are limited to speed 3. They could be better about it, but I've done the same thing when I played as Yor. Sometimes that speed limit can make all the difference between getting a late extreme rush world deep in their territory and finding yourself wondering what to do with a colony ship stuck in the mud in the middle of nowhere.

I've played some TA maps where the Yor didn't take and hold serious territory, but I've played others where they were most definitely a major obstacle to high-speed traffic for me and several other civs. The few times I've played as Yor in TA, I've had no problem building and holding influence turf.

But I'm not really a competitive player desplite the humble MV bling. I almost never try to 'force' a map to a conclusion, I sort of 'ride' them without a very particular destination in mind.