You raise a few interesting points in the story. We never have had a canon suicide attack, if I remember correctly. It would be interesting to establish the motivation for the Death Eaters' suicide attack. Further, with Voldemort gone, who would be fanatic enough to assault Hogwarts with such devastating results? I hope those questions will be answered in the coming chapters.
Nice to see an interesting perspective on the Death Eaters after the fall of Voldemort and the possible reconstruction of Hogwarts. Hope to see some more soon.