[Kowai]

Have any obito=tobi supporters been able to explain their age gap?
How was obito fighting minato?

What if tobi is not only obito's father but madara's son too?

It is clear that tobi is from the hidden leaf because:
He appears to be an uchiha - not confirmed
He had beef with the uchiha - he helped itachi slay the clan (to avenge his father?)
He knows about the various ninja of konoha - kakashi in particular (maybe because he was on his potential son's team) but also shikamaru/the Nara clan (when he steals the jar and shikamaru catches him in kagemane)
Has a relationship with danzo - unknown but who was on danzo's team if hiruzen trained the sannin?

The purpose of his mask is not to hide his identity from the reader (hiding a character we have seen before) but to hide his identity from the other ninja in the story.
So I really really don't see it being obito unless time travel justsu is involved, and although Kishi likes dbz, he doesn't need to go that big of an asspull route.