Harry Potter Prequel First Wizarding War Book Idea?

prequels are good in series like star wars, the chronicles of narnia, and artemis fowl, where some aspect of the background is vague and could use fleshing out. in harry potter, the area you mentioned has already been covered so much that any prequel would just be a rewrite, but would ruin the suspense. although the universe might be good for one or two more books like "tales of beadle the bard"(although even 2 is pushing it), J. K. Rowelling was right to start on a brand new series.