it's actually quite simple why naruto is stronger than sasuke, sasuke has no senjutsu. thats not a fanboy comment, thats just what it is. naruto now possesses the senjutsu of the sage, which is just basically the power of all the bijuu plus a perfect sage mode. which basically means he has now become immune to ninjutsu. every sharingan or rennigan tech is ninjutsu, it uses no natural energy what so ever. But thats not thats not it, the best thing dojutsu have going for it is it's genjutsu. thats basically useless against a perfect jin, especially one that has nine bijuu in him, no way he gets put in a gen. add to the fact that he is able to use all the special jutsu of every respective tail beast, and he is boss. We also can't forget about the little things like the huge speed boost he has, and insane reflexes that are even able to dodge the rinbo hengoku and increased strength
now i understand that we know nothing about the abilities that sasuke has, but there are a few things i know. we know he doesn't have senjutsu. which means that he in fact has to rely on taijutsu if he was to fight naruto. in this battle they are having with naruto it doesn't matter as much as naruto is there to back him up with senjutsi techs. Also, we can't assume that sasuke will get every sharingan or rennigan techs just because he has the jubbi's eye. unlike us assuming naruto can use every bijuu ability it's different, naruto has actually shown the ability to use sons magma so it's more than safe to assume that he can use the others. but since we have literally seen nothing from him, we can't make that assumption. we also know that having eyes do not make you faster or stronger, but he most likely will have advanced perception. That perception is only good if his body possesses the capability of keeping up with his opponent. this is basically why many don't believe they are equal. they may have split the sages power, but that doesn't mean both aspects of the power are equal. also the whole kishi thing, he never said they will always be equal. as a matter of fact when shippuden cam around sasuke was way ahead of naruto, so that means that statement is already false.