Okay, now that I've had a bit of sleep...
Crookshanks was, I am fairly certain, left at the burrow. He was mentioned towards the beginning of the book, I think. And as for the Sorting Hat: Just because something starts on fire, doesn't mean it's destroyed. The hat was ragged to begin with --or perhaps it is someone else's hat with a new sorting enchantment. We'll never know, I guess.
I liked the epilogue --the names of their children (well, Harry and Ginny's) were a little cliche, and I was left wondering who Victoire was? (My Mom and I thought Percy's daughter perhaps?), and it does kind of mean that it is really over. J.K. can finally rest, and she doesn't have to write anymore. She's closed it, and it's done with.
And, while I am not typically an emotional person --I will admit I cried several times while reading, with each death after Dobby's, particularly after Fred's, and then subsequently after you "see" that Remus and Tonks have died. Tears for Severus (though he's my favorite), didn't come until the end of The Prince's Story --which I think is my favorite part of the book. I didn't cry when Harry "died", obviously (I knew he'd live having seen a peek at the epilogue), and I liked Dumbledore's parting words, "Of course it's happening inside your head, Harry, but why on earth should that mean that it is not real?" It made me laugh.
--And that's the other thing I loved about the book --inparticular of the Weasleys. They always could find the humor (case and point: George looses his hear, and can joke about it with Fred) and attempt to lighten the spirits of those around them, and Ron does the same thing, such as when he says, "If we die saving him, I'm going to kill you," to Harry when he attempts to save Malfoy, Crabbe, and Goyle in the Room of Requirement.
Anyway, I best stop while I'm ahead, or I could go on about it for hours and no one wants that, but let me add a big "I concur!" about Mrs. Weasley and her, "NOT MY DAUGHTER, YOU BITCH!" line. Classic.