Kishi says that to every Mnagaka.

Well almost. He list of influence is too long. And you forget that Zabuza had already happened and that's the fight most people still remembered and miss those days.
The most prominent similarity between the two is multilayer of subplot and villains and calculated planning - these two stand out among long running mangas because of it. But the verse are vastly different and even basic values and outlook at the world do not match.
I followed chunnin exams only to find out about Gara 's final fight. The exam lay out itself was not that much of attraction. At least not for me. By the time it ended I noticed Itachi . He immediately struck me as a character about which there was a lot more to come. So it's hard for me to be convinced that examination style was the main attraction of Naruto. It was just a hook for collecting everyone at a right place to give a reason to them to compete in different set ups. At the worst it could have been tournament style.