D&D Mirror Universe

[Bobbyjackcorn]

I've been mulling over this idea since I first saw it posted here and I gotta say, it's still an exciting concept to me.
For me, I like the implication of the mirrorverse just as much as the presentation of the races themselves. For example the core races- as I see it- would still be the heart of civilization. The major countries and cities of the world would belong to evil slave-driving dwarves, insane marauding elves, terrifying corpse-eating gnomes, and whatever humans would be (I'm just scraping them entirely for the campaign I've been planning). Meanwhile, the only bastions of good would be ancient ruins and abandoned cities filled with good-aligned monstrous races. Most gods would likely be evil, because most potential worshippers would also be evil. It'd be a world that is built in an actively anti-good way, and I think that's fascinating.
What do you think about society, and how monstrous races would interact with such a world without the edge that cruelty gives them in a standard world?

[EDIT] BTW, considering how lots of monstrous races have nightvision, and more than a few are nocturnal, do you think that might dramatically effect their culture?