Well, that was the first read that left me completelty underwhelmed.
Ok, in the last few years, the line between Demons and Devils blurred because of cheming Demon Lords.
But it looks to me as if they saw the problem and choose to kick the ball to the other end of the field.
Demons as almost mindless slayers? To me that is not what evil and chaos is. Chaos does not mean stupid. Look at Moorcocks Chaos Gods. They embody Chaos but the are NOT STUPID SAVAGES (only sometimes if it suits them or the mood strikes them).
Evil and Chaos for me is the utter disregard to everything but myself. If I have to destroy the multiverse to get out of my bordeom I will do it without a second thought.
Chaos is everchanging. Today I we plan to infect the material plane with the savage Tide and tomorrow I we start collecting stamps and basball cards.
If I strike a bargain I may honor it but if the mood strikes me I may kill the puny summoner.
I may hatch a plan to take over the abyss taking thousands of years to weave an intricate net only to decide that brute force serves me better.
That is Chaos, unfathomable and everchanging.
The new WoC Demons are only Barbarians with Claws and special Abilities.
And how lame is the Asmodeus story? He killed a God and the God's dying curse turned him into a devil?
Come on, John Milton made a better pitch in 1674 with his Paradise Lost. The Angels were banned from Heaven because the rebelled. It is Satan's Pride that makes him fight against Heaven. It his Pride that makes him defy Heaven even in the Pit (Better to rule in hell than to serve in Heaven). Rather than to serve the newly created man Satan decides to go and tempt Adam and Eve. Sounds better to me than being cursed for killing a God and deciding to be evil and tempt mankind.
And there is even a contradiction in the setting. If Hell is a prison, how can the Devils react "eagerly" to summonings? And if summonings act like summon spells in 3x for only a short duration, how can they form complicated pacts ("Sorry, have to go now, summon time's up, we finish the next paragraph with the next summoning, Cherio")?
And last but not least, why do they use a Greyhawk Deity (Tharizdun) for the generic Points of Light Setting? Is it so hard to whip up another name or is PoL some twisted Greyhawk?
Nope, these ideas are neither original nor creative but a seccond rate mixup of older ideas and thoughts.