Another thing that we could add, [hider= Possible Season 3 Spoiler] is Lin's half-sister Sue. She could be a criminal at this point. [/hider] I think that it would be best to start before their relationship, just because that gives us more to work with, and a more thorough experience. I think that Republic City would be the best setting, although travel might not be the best idea. Especially if Lin is so dedicated to her work. Also, Aang could still be alive, depending on the chronology.