True. If PS made better use of the characters' stories, in addition to providing more backstory and revealing the ideas, thoughts, and how all or almost all of the characters who appear on the island came to be, it would be a fantastic and glorious comic to read. On the other hand, it has stopped with Dylan, Brandi, and Kelly, and has added Victoria and her family.
It would be great to see the backstory of Gina and her family, as well as the rest of the characters.
Allie, for example, could have a very interesting backstory. If it were like the idea you've proposed, it could say that her mother and brother are her biological parents; they could be on the island currently, and that she has grown up in this environment of total sexual freedom and is proud to be born from an incestuous relationship (although that carries risks, of course).
And so, each character could have a very compelling backstory.