Whitebeard's speech is definitely fictionally significant. It can reveal his character, motivations, and influence the plot in meaningful ways. It might also stir emotions among the characters and the audience.
Well, he might become more protective. Just like Whitebeard who was extremely protective of his crew, Naruto could start showing that same level of protectiveness towards his friends and the village. He might be more willing to use his power to shield them from any harm.
Their relationship could develop through mutual respect. Luffy respects Whitebeard as a powerful and respected pirate, and Whitebeard respects Luffy's determination and potential. For example, they could start with a simple exchange of stories about their adventures at sea.
Yes, there might be. The Naruto and One Piece fandoms are both large, and it's not uncommon for fans to create crossovers or fanfictions where characters from one series admire those from another. You can try searching on popular fanfiction websites like FanFiction.net or Archive of Our Own.
Yu Zhouzhou's last words in " Hello, Old Times " were: " The old times at the end, and the hand that held me tightly. In my old times, he was the light."