In this fanfic, Naruto would develop a more refined sense of strategy. Yen Sid's wisdom would rub off on him, and he'd start to think several steps ahead in combat. His relationships with his friends might also change. He could become more of a mentor figure to them, sharing the new knowledge he's gained from Yen Sid. Naruto would also become more in tune with his spiritual side. Learning from Yen Sid, who is likely very attuned to spiritual matters, Naruto would start to explore the deeper meaning of his own ninja way and how it relates to the broader universe.
Naruto's character would develop in several ways. Firstly, his sense of discipline would improve. Yen Sid is a strict teacher, and Naruto would have to follow a strict regimen. This would make him more reliable and less impulsive. Secondly, his understanding of different cultures and powers would grow. Interacting with Yen Sid and his world would expose Naruto to new ways of thinking and being. He'd become more open - minded and adaptable, which are important traits for a hero. And finally, his confidence would be on a different level. Mastering new skills under Yen Sid's tutelage would make him feel more capable of handling any situation.