They Shook Hands/YMMV


 * Ron the Death Eater. The changes in characters aren't immediate.
 * With both Harry being a Slytherin and Ron not meeting him on the train, Ron is set up as a major antagonist to Harry and his friends. Ron looks down on Slytherin, just as he does in canon. He's not evil (yet?) but he is a more extreme version of the canon character.
 * Hagrid is portrayed as an alcoholic rather than someone who has a drink occasionally. The author uses the same incidents of his drinking as are present in the canon, but they are viewed negatively by Harry's friends and thus by Harry.
 * Too Cool to Live: