I'm going to address something I've always found a bit odd. These days, GOOD vs EVUL appears to be a pet peeve of many on the intarwebz, and writers are often discouraged from writing such stories. Likewise, prophecy and chosen ones are hated by many more.
I confess, I love me a top class good vs evil story, with a prophecy. I don't think it is simplistic in its philosophy at all, and if handled well can be brilliant. True, there are some awful ones, but there is awful moral relativism as well. For every poorly executed farmboy, there is a dire anti-hero who we are somehow supposed to sympathize with as he/she murders and eats their mother. Twice.
But I digress a tad, because abusing the poorer examples of moral relativism in fantasy is as farcical as abusing poor good and evil, destiny fantasy.
I love exploring the concept of good and evil. For many, good and evil is an intrinsic part of their world view. Hell, I hope everyone reading this has a definition of right and wrong in their beliefs (if you don't, plz don't stab me).
Are there different kinds of evil? When does someone cross the line? How do you become evil? What is good? Can you be both at the same time?
I would argue traditional good vs evil and moral relativism are two sides of the same coin. They are two different methods of exploring the same subject.
Simple prophecies are boring. But you can flip them around so much. What if they're riddles and almost impossible to decipher? What if there are contradicting prophecies? What if the prophecies are wrong? What if the prophecy predicts salvation at a terrible price, or no certainty of salvation at all?
If there is a chosen one, how do you figure out who he/she is? What does this chosen one have to say about their destiny? Do they meet it at all?
I would hate to see the more traditional elements of fantasy fall by the wayside, because there is always more to say, more to twist. What one writer says will often be completely different to what another says on the same subject.