I don't know what all of the complaints are about - please explain them to me so I can better understand.
When there is character development, there are complaints that there isn't enough action.
Now there is action, there are complaints that Naruto is too powerful.
He used mini-rasenshuriken - which shows more control, not more power.
He used multiple rasengan at once - which also shows more control, not more power.
He has had hundreds of clones, all working together (in teams of two/three can't remember) to do multiple rasengans before - so using multiple does not demonstrate more power. He just has the control that he lacked. Something he learned the past "50 chapters" or "5 hours".
Growth.