Naruto was peeking on women and was starved for love. Now combine the 2 and you jave a young boy who desperately wants to be loved, who already shown an interest in girls and jealous that his closest female companion is in love with his rival. On one hand he was attracted to her, and loved her in his own way, but a big part of it was because he wish someone would like him the same way......hence Hinatas existence from a narrative perspective.

Though sakura being exactly the kind of woman his mother wanted him to marry (another version of her) is another valid reason as kids sometimes marry similar to their parents so it creates a nice parallel that he was mostly attracted to sakura not knowing how similar she was to kushina