The reluctant hero and vengeful son are mythological archetypes. Based upon ancient myths of the same themes (Heracles, for example, or Odysseus) they persevere in modern literature and thrive in a society trained to instant gratification in their entertainment.
Do I have a problem with that? hell, no. I make my living off of it.
However, it's impossible to dismiss Star Wars or Batman as just another set of new variations. Each story has its own distinct world, its own mythical forces, its own theology (for lack of a better word) that directs its characters toward the realms of good or evil.
In my opinion, a modern mythology has to have the same sorts of elements as the great mythological folklores of older societies that are adapted to modern sensibilities. However, every new myth is distinctly its own creation. The world of Star Trek, for example, is people with real, everyday humans who can quote the most obscure trivia points about that world--they don't live there, the world doesn't exist, but for them it's a real, almost tangible existence that lives in their imagination. The personalities of the mythology are larger than life--equating Spock with Odin, for example, is not that big of a stretch--and exist upon a plain that is set above the normal, regular world of the modern human. So, if you're going to build a new myth or mythology, you have to be able to achieve that godlike stature with what you create.
That's why world building is so important in speculative fiction, IMO.