Unless Kishimoto makes some epic-level trollin', which is unlikely- mangaka in Japan need to keep on pumping projects, and their rep is only as good as their last project ended.
So, let's think about this for a second. It's quite simple. The series was about Naruto. Still is, really. Look at the anime. Barely a mention of Sasuke, beyond the whole"must save him".Shit, they are even creating freaking fillers, keeping away the time when sasuke comes back to the forefront.
However, the problem is that Sasuke is popular in Japan. VERY popular, wherein you can tell that at some point you can tell that some directive or his editos just told him"FUCK, Put SASUKE THERE NAO" And boom, endless upon endless moments with Sasuke.
And because he's so popular, and is a villain as well as a character, Kishimoto doesnt wanna treat im' as he would a normal character, who gets defeated, grows up, ect, ect.Becuase a broken and shattered Sasuke, wont be able to be an interesting folly for the final fight againts Naruto.
No, like Neji and Gaara before him, Naruto will break him. But till then, he's going to keep strong.
The only difference here is exposure.
TOo much Sasuke.