1 - Who was Hagoromo's father?
2 - Why hasn't Hagoromo's brother's face been shown, considering that he was strong enough to fight alongside Hagoromo against the Juubi, why hasn't he been mentioned? (maybe killed by Juubi)
3 - How did Kaguya die?
4 - Who will eat the Fruit?
5 - What is Orochimaru and Kabuto's real goal?
6 - Who was Uzumaki Arashi?
7 - Will Sakura ever be useful?
1. Don't know maybe Kaguya did it herself or something.
2. Probably fodder like Itama or Madara's other brothers. Kishi too lazy to develop him or something.
3. Old age
4. Have to wait.
5. Kabuto wants peace now I guess. Oro don't know.
6. Fodder or translation error.
7. She is already. Helped beat Sasori, healed army, pumped Naruto's heart.