If he gets the Rinnegan it will be in a bodily aspect, much of his fans would be trolled if he gets concentric circle eyes. The Uzumaki symbols while he is using RM would most likely change into Rinnegan circles. If he gets the Rinnegan it wont be like other users, Rinnegan has been shown to be different in every user it isnt a pre-defined technique but something that adapts to the user, the Rinnegan was outright transplanted to Nagato so Nagato could only use the pre-set Rinngan abilities, Madara awakened somehow so he is able to combine it with his Uchiha previous powers to form new techniqus like the method.
If Naruto has it, he will most likely adapt it to his bodily powers. The Rinnegan would most likely be used to further strenghten his chakra and give super sealing techniques or something.