Huh, that's interesting. And I agree, why wouldn't you wonder and elaborate and think about what happens next? Why wouldn't you want to wander more around Amestris or come up with a way for this plot point and that one to actually make sense in the canon? Or write what would have happened if So-and-So had lived, and impacted the life of the protagonists?

I agree with dameruth on RPS (I actually have the same squicks, sometimes extending towards fictional characters, oddly), but fiction? Fiction is a playground.