Board Thread:Theories and Speculation/@comment-1872728-20160229033316/@comment-26773508-20160307064240

QuakingStar wrote: Being a Jinchuriki is the only reason he is, but yes he is now. Don't forget free Hagoromo powerups. Naruto is probably the most unimpressive protagonist in the manga world.

On topic: I like the OP's theory, though I am sceptical about it thanks to the manga lore. As others have pointed out, almost all the known descendants of Hagoromo and Hamura have very sharp and defining characteristics, except for the Senju. The Uchiha have their God-level-Cheat eyeballs; the Hyuuga and the Moon Otsutsuki had the "So Much Potential But Totally Underdeveloped" White Eyes; select members of the Kaguya Clan had a watered-down version of Kaguya's Ash Killing Bones or whatever it's called; and the Uzumaki had their incredibly powerful chakra, enhanced healing, Charkra Chains suitable for suppressing Bijuus, and their red hair. The Senjus don't stand out at all, except for Hashirama.

Considering these characteristics of the Uzumaki, it seems sensible to assume that the Uzumaki bred far more purely than the Senjus, who probably said "Fuck You!!" to arranged, endogamous marriages and eloped with whoever the fuck they wanted (except for the Uchihas and the Hyuugas), hence watering down their once-sharply defined characteristics. On the plus side, the Senju probably inherited such a wide variety of genetic characteristics and abilities through their free intermingling that, in all probability, ultimately led them gaining the nickname "The Clan of a Thousand Jutsus". In the real world, genetic diversity in a group is always a huge advantage, while groups with less genetic diversity are much more likely to end up in the wrong side of Natural Selection.

Of course, the shinobi world is different and hence, the same rules of genetics may not apply. Also, there is no evidence in the manga whatsoever about the particular speculations the OP and some others (including me) are indulging in. But one thing is clear: Kishi's treatment of the Senju is the most unsatisfactory among Kaguya's descendants. They just haven't been given any special characteristics that make them stand out, except for the implication made throughout the manga that the Senju had huge chakra reserves. But the 3rd and 4th Raikages naturally possessed Bijuu-level chakras too, not to mention totally badass bodies that can tank even Sage Art: Rasenshuriken. So Senju characteristics are way too nebulous to be satisfactory.