You are basing this on specific events.
1) Naruto was watching Obito becoming the Jinchuriki, whereas Sasuke was in the middle of fighting him, and had a poor vantage point
2) Naruto knows sage mode, Sasuke doesn't
3) Sasuke asked Naruto what the next movwe would be b/c Naruto is the one with SM
4) Since Madara didn't have Rinnegan, there was no reason to assume Amaterasu wouldn't work
5) Minato praised Sasuke for his intelligence. Also,Naruto tried to attack Obito with a tbb, even AFTER he knew that only SM worked.
If you look at Sasuke's fights,he is much better as assessing the situation and planning ahead than Naruto is.