I am of the opinion that the term "borrowed power" is contrived, because none of the characters in the story proper ever mention it. There is no need for fans of either character to be upset, because Naruto and Sasuke are simply being true to their characterizations and characters themselves.
I will state plainly that I think Sasuke currently has more power than Naruto, at least in the typical sense when one thinks about the word. This is not something to be alarmed about, because being upset about this is actually an insult to Naruto himself. Let us consider what Sasuke is. He is the end result of countless generations of the reincarnation of a man that viewed "power" (in the tangible sense) to be superior to everything. Madara, the previous reincarnation, also said the same thing to the 5 kage, saying that power is something that is tangible, as opposed to Tsunade's view that the will of fire was power. Therefore it is totally understandable that Sasuke would eventually reach the pinnacle of power as he has now. He is in possession of the strongest eyes, and through utilizing his susanoo as a makeshift gedo mazo, has essentially gained the powers of the ten tailed beast. To him, they are just power. The very will of his chakra is to stand at the top in terms of power, and he is being true to it.
In comparison, Naruto is the end result of countless generations of the reincarnation of a man that viewed love to be superior to all. As a result, him lacking less power than Sasuke (once again, at least in typical terms) is acceptable, because it is not important to him. BUT, what he lacks in tangible power he more than makes up in the power of the heart. He has the "power" to unite people through nothing more than the gravity of his personality, flaws included. He needed the help of the shinobit alliance, the bijuu, and in the future he will most certainly depend on others. But that is who he is. The will of HIS chakra is to use love and cooperation as the reason and endpoint for his actions. And, what makes him unique as a reincarnation is that he has NOT come to the point where he is willing to sacrifice the current reincarnation of Indra in the name of a greater goal, like Ashura and Hashirama before him. And that is why he is the protagonist that Hagoromo, and Kishimoto entrusted the future to.
To conclude this, render unto Caesar that which is Caesar's, that is to say, appreciate Sasuke for his overwhelming power. Sasuke is a representation of "the power of power," and it is therefore not a bad thing him being more powerful than Naruto, which should help him appeal to his fans. On the other hand, Naruto is a representation of "the power of love," and though he is tangibly weaker than Sasuke, it is his spiral of the power of love (using his feelings to give him strength, and in turn using his strength to protect his feelings) that may ultimately lead to his victory. While being inferior in "power," him attaining victory is what should make him appeal to HIS fans.
What do you think?
