Disclaimer: Naruto isn't mine
Being a dad means not being able to put your newborn baby down.
There are few moments in life that can be described as perfect. There are few things in life that can be described as perfect. Even things we may claim are perfect, really aren't. They are our subconscious way of tricking us into thinking we have experienced a perfect moment or see a perfect item. When we do have a perfect moment or see a perfect object our brain becomes overwhelmed with the idea of perfection and how one simple object/thing can be the very essence of it.
One thing that Sasuke could guarantee was perfect. The birth of his first born daughter. His first child. The first member of the newly revived Uchiha clan. The best thing that had ever happened to him. She was perfect. She was a symbol that the Uchihas were once again a name to be reckoned with.
She was truly perfect.