Board Thread:Naruto News/@comment-27939371-20160308173951/@comment-4646462-20160308191636

Rasenshuriken is thrown, which negates the side-effects that using it like a Rasengan brought.

Wind Release: Rasengan is just the base form of the technique. Frankly, I myself am not sure why Naruto didn't use it more, as it takes less chakra to form than a Rasenshuriken, and while it does cause damage to himself, it's nowhere near the same degree that the Rasenshuriken did. Either way, its usefulness was thrown out the window once Naruto started throwing Rasenshurikens, especially now that Naruto, as an adult, can form and throw them in an instant and en-masse with only his base chakra.