I just (as in, about an hour ago) finished re-reading _Deathly Hallows_ as i had read it so quickly the first time it was almost skimming. (seriously, i remembered Snape's love, and Narcissa's love, and all the horcruxes, and seemingly everyone dying but other than that...)
The thing that is sticking with me right now? How did Neville get the sword of Gryffindor for the final battle? He clearly didn't have it until the very, very end and there's zero explanation as to how/why Griphook would have ever EVER relinquished a goblin treasure. Sure it was helpful, but Ron and Hermione also had armfuls o basilisk fangs which would have been just as effective.
The book is not judgy on Hermione wiping her parents' memories. She is upset about having to do it to protect them, but there is no judging from any other characters, who seem to perceive her misery over having done it as her being slightly melodramatic. The movie treats it very touchingly, and there is evident grief in her actions.
How do we know that Neville married Hannah Abbot? The spilogue mentions him as a Professor of Herbology but not his personal life. I kinda assumed he and Luna ended up together, because that would just be so pat.
edited to correct improper use of an apostrophe. cuz that'd be catastrophic. (in my mind, that was a word play on "apostrophe" but it doesn't scan in print.)