To me, the fact that the boundaries have no reasonable relationship to PQ is also off-feeling. The modest morale bonus for high PQ worlds might be an adequate compromise, but IMO the math for these angry-horde dropoff points should be directly based on PQ. Every additional tile should enable that much more room for shiny, happy people.
i agree, that's an entirely reasonable stance. i think it's the boundaries themselves that i dislike. i think i dislike the way the relationship between population and morale is implemented. i would prefer to see morale penalties for high pop happen on an empire wide level as well as a planetary one, the same way there are parallel empire/planet morale bonuses. it also seems more realistic to me. i'll elaborate.
empire-wide morale bonuses are usually described in-game as some sort of commoditiy. either the "goo" you extract from mining resources or some sort of manufactured good, like VR modules. as commodities, they'd be in limited supply, and therefore as empire-wide population increases, they should have less effect (or you should need more of them to have the same effect). i dislike the approach of having a hard cap on empire-wide morale.
on the planetary level, too, it's disconcerting that plantary conditions become utterly intolerable after you exceed 20 billion. while i agree that it should become more difficult, even perhaps exponentially so, it's awkward that it's at seemingly arbitrary intervals rather than a smooth, curved of morale penalty.
/2 cents.