Why did Madara specifically choose Nagato to implant his Rinnegan in? Did I miss something? Did Nagato have anything special about him before he acquired the Rinnegan?
he had really strong chakra and is from the senju lineage the uzumaki clan. he had a better chance of having better control with the eyes then mostly any1
simple
since Uzumakis are the best option for being a jinchuriki, that goes for rinnegan too
rinnegan tech use lots of chakra
see what happened when nagato used gedo-mazu or rinne tensei