Epilogue was a fake. It was a hoax by Rowling and any information released since then is just her trying to fuck with your head.

I like the idea, It's got potential as long as you keep the characters believable.

 

Because Tracy is fugly and we all like Daphne anyway.

The idea is ok but it sounds too much like a basis for the all too familiar Harry!Harem fics I've read. I gon't think Ginny works too well as a dark person, the kind of person she was when she was a child totally contradict what falling to the darkness would be like. Despitee how stupid and inbred the Weasleys are, even they would notice a bubbly, talkative child going dark.

As to Harry!Slytherin chick friendships...that never works. Unless you could find an incredibly believable reason for Harry to go back on his hate of Slytherin and drift away from his best friends then it's fail in my opnion. Puberty is a vaguely ok reason but I doubt Harry would go for a Slytherin girl he has never spoken to instead of some other Hogwarts hottie.

I guess though, it could turn into a good, enjoyable read if you got time on your hands, especially if you can find a way to make the characters work. Nothing hugely different though.