I think that even if Obito and Rin would have survived , Rin would be in love with Kakashi and would have friendzoned Obito.
We know that Uchiha are emotional sensitive. So Obito could become darker , I imagine a relationship between Kakashi and Obito like Hiruzen and Danzo. The both are friends , but one is jealous.
And as Obito would be weaker , never he could become Hokage. Minato without Kyuubi's attack would be Hokage for long time like Hiruzen , and the successor would be Naruto or Sasuke or other powerful shinobi of Naruto's generation.
Itachi also could be the successor.
Obito would be just a simple Jonin.
So we can imagine that Obito would become evil , or would be a Dark Konoha shinobi like Orochimaru or Danzo.
We know that Uchiha are emotional sensitive. So Obito could become darker , I imagine a relationship between Kakashi and Obito like Hiruzen and Danzo. The both are friends , but one is jealous.
And as Obito would be weaker , never he could become Hokage. Minato without Kyuubi's attack would be Hokage for long time like Hiruzen , and the successor would be Naruto or Sasuke or other powerful shinobi of Naruto's generation.
Itachi also could be the successor.
Obito would be just a simple Jonin.
So we can imagine that Obito would become evil , or would be a Dark Konoha shinobi like Orochimaru or Danzo.