I can give a reason Hiro went to that time: The world exploded there. He couldn't have traveled any further into the future.
Well he may have gone further. But if the world really did explode, Hiro would find himself floating in space.
Hiro leaping to that exact moment reminds me of other shows...like Quantum Leap, or Doctor Who. Where the main character always jumps to some pivotal moment in time where they're needed.
But in those shows it's suggested that something is deliberately sending them there. With Doctor Who it's his ship the Tardis. In Quantum Leap it was always suggested that it was actually God.
And you're right, Heroes has always had this pseudo religious undertone. What with suggestions that everything is happening for a reason, and the unexplained symbol appearing over, and over. And now the painting of the Earth exploding shown in at least two different locations.
It doesn't bother me that the show is suggesting that some supreme being may be work, I just don't like it when characters start getting preachy. I don't watch these shows to hear a sermon.
For instance, I love the show "Lost". In the beginning my favorite character was Locke. He was tough and cool...a bad-ass. But them he started becoming obsessed with his belief in destiny, and the Island manipulating it. And even though he seems to be right, it still annoys me that the writers turned him into a fanatic for yet another false religion.
That said, personally I think that Nathan's being manipulated by someone. Linderman perhaps. And speaking of Linderman, anyone have any ideas why he's not dead?