Loving the Utopia release. In my second playthrough, I saw a huge bordering empire disintegrate into two separate nations. EU4 style, but in space. Very cool. Wish I had the save game. Felt ultra-epic, a real space opera 
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But this only happened once in three separate games and about 12 hours of gameplay (I did notice a few smaller planets shift here and there, potentially through political rebellion). If the AI is managing to reliably keep wide and diverse empires together without player minmaxing, then that's a pretty strong argument that keeping factions happy is probably too easy.
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It'd be great if massive intergalactic nations broke up more frequently, and would serve to further balance wide vs. tall, as well as making for interesting galactic storylines. Not sure on the mechanics, but probably by making factional/planet rebellion more common would do the trick. And thank you Paradox for making an awesome game and dlc
.But this only happened once in three separate games and about 12 hours of gameplay (I did notice a few smaller planets shift here and there, potentially through political rebellion). If the AI is managing to reliably keep wide and diverse empires together without player minmaxing, then that's a pretty strong argument that keeping factions happy is probably too easy.
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It'd be great if massive intergalactic nations broke up more frequently, and would serve to further balance wide vs. tall, as well as making for interesting galactic storylines. Not sure on the mechanics, but probably by making factional/planet rebellion more common would do the trick. And thank you Paradox for making an awesome game and dlc