Harry Potter and the Prisoner of Azkaban question

Why not write Dumbledore's biography (not from Rita Skeeter's poisoned pen)? Why not write about the founding of Hogwarts? I have a theory that Dumbledore is a phoenix so you could write about the many lives and successes of the greatest wizard ever...

I'd definitely want to see the back stories. I think focusing on James in particular would be really interesting.
Not to say that Harry's kids wouldn't be worth reading about, but Voldemort is gone at that point, and I think that they will actually be allowed to be kids unlike Harry was at that age. Which, to me seems like it wouldn't be that fascinating of a read since it would probably consist of alot of middle school and high school drama. Maybe a short story or something, would be a good idea, just for the update, but I don't think it would make a great series. And after the original, it would be a huge let down.

There is a James Potter series, and, from what I understand, J. K. Rowling gave the author her endorsement. I have not yet read the series, but I hear it's pretty good (Nothing on HP of course).

Perhaps the James Potter series is fan fiction?

Google is my BFF!!

The series is right here at Goodreads. I would classify it as fan fiction. It's about James Sirius Potter, Harry's first born. JKR has given it a nod and WB is ignoring it.

HARRY"S KIDS!!!!

I don't know if I would like another book in this series. The ending was, in my opinion, perfect. BUT I wouldn't say no to hear that she was writing another book about Harry Potter. I would like to know what he's doing on a normal day today and how he is doing in his job, how family life is, etc.

I think I would rather read something about the marauders era because that would also be the beginning of Voldemort. On the other hand, you already know how it would end. But I would generally read a book set in that universe, maybe something about a completely unrelated character would be great.

I would like a series about a different person in the same universe at a different time.

Marauders. Definitely.