Naruto's intelligent. Wait i ask Kurama who see what Naruto see. And know how his brain work.
Kurama said he could be the idiot that SO6P mentioned.
Kurama said "He has powerful pair of eyes and he has took my chakra so that he has the speed."
His eyes is sharp and able to see certain things that others had missed -fight with 3rd Raikage. No need for Sharingan or Rinnegan eye.
To defeat 3rd Raikage, he need both eyes and speed. If his speed was slower than Raikage, Naruto die. If his eyes and hand reflex was slow, he cannot aim his rasengan direct to the target position. But smart enough by use clone, which was Kakashi's idea. And also use clone to test Madara power.
But for planning any action, Naruto is a idiot. So, Kurama took over Naruto and seize control as "Captain" that Kakashi & Guy surprise, but happy. Kurama told them "Now, i tell you what to do, because i know Juubi power". And Naruto became the shadow of Kurama.
Naruto alone had intelligent at 50%. And + Kurama 50% = 100%.
Naruto was always being knock down, maybe the idea was to know his opponent' power & strength.
Naruto is something like, Madara and Kakashi, wanting to test the opponent.
Conclusion: Minato sealed Kurama yang chakra to give him the powerful Kurama's speed, which Minato cannot teaches him.
Beside Kurama chakra, he gained Kushina's chakra, as what Kakashi told Naruto about his plenty of chakra.
Naruto's intelligent = 50% same as ordinary...........................