I don't think that the fight between them is going to be what everybody thinks. It's not going to be a fight to the death, but rather a a fight to see who is stronger.
That being said, Naruto is clearly stronger than Sasuke. He may initially pull some punches and go easy, but if Sasuke is serious about harming the village and all of Naruto's friends, comrades, etc. then Naruto will likely step up his game, too. Naruto may not be determined to kill Sasuke, but he will protect his allies and village at any cost, and if that means that Sasuke is going to die, then so be it. Naruto even said that if they meet in battle, they are both going to die.
Furthermore, EMS doesn't put Sasuke anywhere near Naruto's level. Sasuke can barely use genjutsu. It has been stated that a Jinchuriki who is in sync with his/her Bijuu cannot be beaten by genjutsu anyways. Amaterasu can burn physical objects, but Naruto's Chakra Cloak is not a physical entity. Much like Nagato pushed Itachi's Amaterasu away with chakra (Almighty Push), Naruto is probably able to dispel Amaterasu by disengaging his cloak or expelling excess chakra from the cloak. This leaves Sasuke's Susanoo, which is the weakest form that we've seen in the series thus far. Itachi could seal pretty much anybody with his Susanoo and Madara can stabilize his into a Perfect form. Sasuke could barely maintain a complete Susanoo (with armor) while fighting Danzo. Plus, Sasuke's Susanoo seems to be slower than the other two. Maybe he's improved since his fight with Danzo, but he was all but helpless when he and Itachi fought against Kabuto.
As for Sasuke's "so many" other techniques. Which ones were you referring to? Sasuke has used a handful of fire techniques,variations of the Chidori, and Kirin. Every single one of Sasuke's electrical attacks are a form of Chidori/Lightning Blade except for Kirin. Kirin also takes a huge amount of time to prepare and leaves Sasuke pretty much helpless afterward. All of Sasuke's fire techniques seem to be variations of the Fireball Jutsu or Phoenix Flower Jutsu. In short, Sasuke is strong in his own right, but if you claim that Naruto only spams the Rasengan, you have to address the fact that Sasuke does the same thing with Chidori/Lightning Blade. Furthermore, you can't just say that Sasuke can perform techniques (like Perfect Susanoo) before he actually demonstrates them in the series.