Luffy might be excited to have a new member, as he always is about making new friends. But he's also not stupid, he would keep an eye on Kuro. Zoro would be very skeptical. He doesn't trust easily, especially someone with Kuro's reputation. Nami would probably try to figure out how she can benefit from Kuro's skills, while also being cautious not to be double - crossed.
If Naruto was raised by the Straw Hats, he'd probably be a very different person. He might be more carefree like Luffy. For example, he'd be used to the wacky adventures on the Grand Line. His ninja skills could blend with the pirates' combat styles, creating some really unique fighting techniques.
Well, as of the latest manga chapters, Yamato has indeed become a part of the Straw Hats. This decision brings new dynamics and adventures to the crew.
His personality would become more outgoing and adventurous. The Straw Hats' lifestyle is full of exploration, so Naruto would be more eager to take risks.
I really like the fanfiction where the Straw Hats time travel to the future. In this story, they see how their actions have affected the world in the long run. It shows a post - apocalyptic world that was caused by a series of events that they were unknowingly a part of. It makes them reflect on their current actions and how they can change things for the better. Another good one is the one where they go back to the time of Gol D. Roger. They get to meet the legendary pirate and learn some of his secrets, which is really exciting for fans of the series.
Well, in this fanfiction, the Straw Hats might be in need of a powerful ally. They meet Hancock, and she is instantly drawn to Luffy. The crew could then face a common enemy that is threatening both Amazon Lily and their own goals. Hancock decides to join forces with the Straw Hats. Sanji would be over the moon to have Hancock around, but also a bit jealous of Luffy's special connection with her. And Zoro would be his usual stoic self, just glad to have extra muscle for the upcoming battles.
Kizaru could also be interesting. His light - based powers are extremely powerful. If he joined the Straw Hats, he could use his speed and laser - like attacks to protect the crew. However, he would need to change his loyalty from the World Government, which could create a complex and engaging storyline.
At first, not very well. The Straw Hats have had bad experiences with Marines. They might see the Marine OC as a potential threat. However, if the OC shows that they are different from the typical corrupt Marines, like by helping the crew out of a tough situation right away, they might start to be more accepting.