I'm a well read grad student who's bluntly honest about all things, although I try to be most honest about myself.
Black Bolt, Maximus and Medusa remain in New York, practicing, trying to figure out if they can trust Elisha, the Alpha Primative, and trying to figure out how to get to Attilan without dying as soon as they get there. (Or Medusa may survive, but it's not likely that Black Bolt and Maximus will.)
Meanwhile, a young Crystal is distraught over the loss of her dog, Lockjaw, who was responsible for bringing the trio to New York. She tells Gorgon that they're missing and how Medusa followed Black Bolt (and to a lesser degree Maximus), although these might only be rumors, at least from Gorgon's point of view. In New York, Lockjaw teleports, presumably because he senses Crystal's despair and goes back to her, although this isn't revealed yet.
Maximus is running out of the pills that keep him sane, and this is new - both the concept that Attilan has drugs for - or any way at all to deal with - psychological problems or mental health issues at all, and the fact that Maximus wants to stay mentally healthy and and sane. These are fascinating concepts since they seem retconned in and I question why these are never followed through with later on in Maximus' past.
Nothing much about what's happening with Triton and Karnak, although there's more about how Triton went through terrigenisis. Another twist: it's always been portrayed as Triton and Karnak's parents who kept Karnak from going through the process, but here he sneers at it. It's superstition, and ritual, and the Inhumans are supposed to be scientific. He also isn't afraid of Triton when he comes out of terrigenesis - again, his parents have always been portrayed as freaking out which kept them from putting Karnak through the process - but rather a 'look, see what we've wrought with this' type of attitude.
Definitely a mix of original history and retcon, but the retcons are so far very much superior to the original tale, so I can't find it in myself to care that Priest is changing so much.