Well, if you realistic as much as you can in anime WWW, luffy's super powerful. Especially now, with his new busoshoku. But his powers and techniques are just not as versatile and explosives. Naruto can shoot hands as big as gear third from everywhere in his body, and unlike luffy who's techniques are very similar with different names and enhancement to them, with his only way of fighting is punching and kicking and headbutting, naruto's versatility of close and long range, with different kinds of abilities and techniques, give him an edge. Best example I think would be how naruto dealt with madara's meteor, madara's limbo and kaguya in the ice dimension. Luffy's the purest beat 'em up character, he'll just charge in, no deception or tricking, just punch his way through. He would have deal with the meteors same way he dealt with Noah, punching them to dust. But there werr too many for him to keep shifting place between them and destroy them all in time. Naruto just launched separated attacks all at once, because he got more than just his two bare hands. I think it's pretty cool though, the way luffy does, despite all his strength and power, on the basis remained exactly what he is, a fist fighter, but that wouldn't cut it in this situation. Same with madara's limbo, let's ignore the fact that you gotta have 6P Senjutsu to hit, naruto had the versatility to use sealing immobilising rasengan and pin it down with the TSB. Luffy's only way of immobilizing his enemy is knocking them out or literally wrap himself around them like he did to that poor soldier in enies lobby. With kaguya, naruto used trickery and put up fight, just enough to convince he does fighting, and let her catch him with the icebergs. Then he let her get close to unleash another of his arsenal, the vapor style from kokuo, to break free and overwhelm kaguya when she came close with her guard down. Luffy wouldn't do something like that, nor he could. He wouldn't let himself get trapped, with till the opponent get close enough and take him down by surprise, not to mention he doesn't have such random and miscellaneous ability like unleashing steam to melt the ice and use it's pressure to overwhelm kaguya momentarily when she let her guard down. So, I think luffy can put up a good fight, but I think naruto's versatility and fighting style that actually include strategies and analyzing the opponent would eventually overwhelm luffy's beat 'em up approach. (Sorry for the long comment. I just get very worked up about these kind of things, because naruto and one piece are headbutting inside my head all the time for my favorite anime spot). Also, so I won't get crucified, I want to make sure that I love and appreciate both characters. Already made the mistake of not making that clear once.
